Fracturing fluid property play a critical role in developing unconventional reservoirs.Deep eutectic solvents(DESs)show fascinating potential for property improvement of clean fracturing fluids(CFFs)due to their low-p...Fracturing fluid property play a critical role in developing unconventional reservoirs.Deep eutectic solvents(DESs)show fascinating potential for property improvement of clean fracturing fluids(CFFs)due to their low-price,low-toxicity,chemical stability and flexible designability.In this work,DESs were synthesized by mixing hydrogen bond acceptors(HBAs)and a given hydrogen bond donor(HBD)to explore their underlying influence on CFF properties based on the intermolecular interactions.The hydrogen-bonding,van der Waals and electrostatic interactions between DES components and surfactants improved the CFF properties by promoting the arrangement of surfactants at interface and enhancing the micelle network strength.The HBD enhanced the resistance of CFF for Ca^(2+) due to coordination-bonding interaction.The DESs composed of choline chloride(ChCl)and malonic acid show great enhancement for surface,rheology,temperature resistance,salt tolerance,drag reduction,and gel-breaking performance of CFFs.The DESs also improved the gel-breaking CFF-oil interactions,increasing the imbibition efficiencies to 44.2%in 74 h.Adjusting HBAs can effectively strengthen the intermolecular interactions(e.g.,HBA-surfactant and HBD-surfactant interactions)to improve CFF properties.The DESs developed in this study provide a novel strategy to intensify CFF properties.展开更多
Molecular self-assembly is extremely important in many fields, but the characterization of their corresponding intermolecular interactions is still lacking. The C-H stretching Raman band can reflect the hydrophobic in...Molecular self-assembly is extremely important in many fields, but the characterization of their corresponding intermolecular interactions is still lacking. The C-H stretching Raman band can reflect the hydrophobic interactions during the self-assembly process of sodium dodecyl sulfate （SDS） in aqueous solutions. However, the Raman spectra in this region are seriously overlapped by the OH stretching band of water. In this work, vertically polarized Raman spectra were used to improve the detection sensitivity of spectra of C-H region for the first time. The spectral results showed that the first critical micelle concentration and the second critical micelle concentration of SDS in water were 8.5 and 69 mmol/L, respectively, which were consistent with the results given by surface tension measurements. Because of the high sensitivity of vertically polarized Raman spectra, the critical micelle concentration of SDS in a relatively high concentration of salt solution could be obtained in our experiment. The two critical concentrations of SDS in 100 mmol/L NaCl solution were recorded to be 1.8 and 16.5 mmol/L, respectively. Through comparing the spectra and surface tension of SDS in water and in NaCl solution, the self-assembly process in bulk phase and at interface were discussed. The interactions among salt ions, SDS and water molecules were also analyzed. These results demonstrated the vertically polarized Raman spectra could be employed to study the self-assembly process of SDS in water.展开更多
Organic batteries have attracted a lot of attention due to the advantages of flexibility,light weight,vast resources,low cost,recyclability,and ease to be functionalized through molecular design.The biggest difference...Organic batteries have attracted a lot of attention due to the advantages of flexibility,light weight,vast resources,low cost,recyclability,and ease to be functionalized through molecular design.The biggest difference between organic materials and inorganic materials is the relatively weak intermolecular interactions in organic materials but strong covalent or ionic bonds in inorganic materials,which is the inherent reason of their different physiochemical and electrochemical characteristics.Therefore,the relatively weak intermolecular interactions can indisputably affect the electrochemical performance of organic batteries significantly.Herein,the intermolecular interactions that are closely related to organic redox-active materials and unique in organic batteries are summarized into three parts:1)between neighbor active molecules,2)between active molecules and the conduction additives,and 3)between active molecules and the binders.We hope this short review can give a distinct viewpoint for better understanding the internal reasons of high-performance batteries and stimulate the deep studies of relatively weak intermolecular interactions for strengthening the performance of organic batteries.展开更多
Intermolecular interactions and properties of TNT（2,4,6-trinitrotoluene）/CL-20（2,4,6,8,10,12-hexanitrohexaazaisowurtzitane） cocrystal were studied by density functional theory（DFT） methods. Binding energy, natur...Intermolecular interactions and properties of TNT（2,4,6-trinitrotoluene）/CL-20（2,4,6,8,10,12-hexanitrohexaazaisowurtzitane） cocrystal were studied by density functional theory（DFT） methods. Binding energy, natural bond orbital（NBO）, and atom in molecules（AIM） analysis were performed to investigate the intermolecular interactions in the cocrystal. Results show that the unconventional CH···O type hydrogen bond plays a key role in forming the cocrystal. The variation tendency of entropy and enthalpy shows that the formation of the cocrystal is an exothermic process and low temperature will be benefit for the assembling of complexes. The calculated detonation velocity of the cocrystal agrees well with the experimental value which is higher than that of the physical mixture of TNT and CL-20. In addition, bond dissociation energies（BDEs） of the weakest trigger bond in TNT/CL-20 complex were calculated and the results show that the TNT/CL-20 complex is thermally stable. Finally, first-principles calculations were performed and analysis of the nitro group Mulliken charge indicates that the cocrystal is less sensitive than pure CL-20.展开更多
Ab initio calculations at the B3LYP/3-21G^(**), HF/3-21G>^(**) and ONIOM(HF/3-21G^(**): AM1) levels of the theory in combination with counterpoise procedure for BSSE correction were performed on HMX dimers. There e...Ab initio calculations at the B3LYP/3-21G^(**), HF/3-21G>^(**) and ONIOM(HF/3-21G^(**): AM1) levels of the theory in combination with counterpoise procedure for BSSE correction were performed on HMX dimers. There exist two O...H intermolecular contacts and the dispersion forces are dominant in the dimers. The corrected binding energies of the dimer are -15.10 and -17.81 kJ/mol at the HF/3-21G^(**) and \{ONIOM(HF/3-21G^(**): AM1) \}levels, respectively. The calculation by the B3LYP method gives irrational corrected binding energies though it produces similar intermolecular distances as those produced by the HF or \{ONIOM\} method. The geometrical parameters, the contact distances and the binding energies demonstrated, for the first time, the validity of the ONIOM method applied in the calculation of the parameters of intermolecular interactions.展开更多
Five fully optimized structures of complexes between aza-calix[6]arene host monomers（Ma～Me） and complexes（a～e） have been obtained at the B3LYP/6-31G（d） level.Natural bond orbital（NBO） analysis was performed ...Five fully optimized structures of complexes between aza-calix[6]arene host monomers（Ma～Me） and complexes（a～e） have been obtained at the B3LYP/6-31G（d） level.Natural bond orbital（NBO） analysis was performed to reveal the origin of the interaction.The intermolecular interaction energy was evaluated with basis set superposition error correction（BSSE） and zero point energy correction（ZPEC）.The B3LYP/6-31G（d） calculations on the five complexes have shown that the greatest interaction（–13.98 kJ/mol） is found in the complex between HMX and hexa-aza-calix[3]-p-tri-arene[3]-2-amido-1,3,5-tri-azine.The results have indicated that intermolecular interaction energies of aza-calix[6]arenes with substituted group are stronger than those without substituted group,and those with amido are greater than with nitryl.Thus,hexa-azacalix[3]-p-tri-arene[3]-2-amido-1,3,5-tri-azine is rather equal to eliminate HMX from explosive waste water.展开更多
Tetrazole monomers （Ⅰ, Ⅱ） and all of their possible stable dimers （1, 2, 3, 4, 5, 6, 7 and 8） were fully optimized by DFT method at the B3LYP/6-311＋＋G^＊＊ level. Among the eight dimers, there were two 1H-tetr...Tetrazole monomers （Ⅰ, Ⅱ） and all of their possible stable dimers （1, 2, 3, 4, 5, 6, 7 and 8） were fully optimized by DFT method at the B3LYP/6-311＋＋G^＊＊ level. Among the eight dimers, there were two 1H-tetrazole dimers, three 2H-tetrazole dimers and three hetero dimers of 1H-tetrazole and 2H-tetrazole. Vibrational frequencies were calculated to ascertain that each structure was stable （no imaginary frequencies）. The basis set superposition errors （BSSE） are 2.78, 2.28, 2.97, 2.75, 2.74, 2.18, 1.23 and 3.10 kJ/mol, and the zero point energy （ZPE） corrections for the interaction energies are 4.88, 4.18, 3.87, 3.65, 3.54, 3.22, 2.87 and 4.34 kJ/mol for 1, 2, 3, 4, 5, 6, 7 and 8, respectively. After BSSE and ZPE corrections, the greatest corrected intermolecular interaction energy of the dimers is -43.71 kJ/mol. The charge redistribution mainly occurs on the adjacent N-H…N atoms between submolecules. The charge transfer between two subsystems is very small. Natural bond orbital （NBO） analysis was performed to reveal the origin of the interaction. Based on the statistical thermodynamic method, the standard thermodynamic functions, heat capacities （C^0P）, entropies （S^0T） and thermal corrections to enthalpy （H^0T）, and the changes of thermodynamic properties from monomer to dimer in the temperature range of 200.00 K to 700 K have been obtained. 1H-tetrazole monomer can spontaneously turn into two stable dimers at 298.15 K.展开更多
Seven optimized configurations and their electronic structures of 4-amino-5-nitro- 1,2,3-triazole dimers on their potential energy surface have been obtained by using density functional theory （DPT） method at the B3...Seven optimized configurations and their electronic structures of 4-amino-5-nitro- 1,2,3-triazole dimers on their potential energy surface have been obtained by using density functional theory （DPT） method at the B3LYP/6-311＋＋G＊＊ level. The maximum intermolecular interaction energy is -35.42 kJ/mol via the basis set superposition error-correction （BSSE） and zero point energy-correction （ZPE）. Charge transfers between the two subsystems are small. The vibration analysis of optimized configurations was performed, and the thermodynamic property changes from monomer to dimer have been obtained with the temperature ranging from 200 to 800 K on the basis of statistical thermodynamics. It is found that the hydrogen bonds contribute to the dimers dominantly, and the extent of intermolecular interaction is mainly determined by the hydrogen bonds＇ strength rather than their number. The dimerization processes of Ⅳ, Ⅴand Ⅵ can occur spontaneously at 200 K.展开更多
The structures,the binding energies and the thermodynamic properties of formamide and hydroxyacetonitrile(HAN) dimers have been studied by means of the self\|consistent \%ab initio\% Hartree\|Fock and the second\|orde...The structures,the binding energies and the thermodynamic properties of formamide and hydroxyacetonitrile(HAN) dimers have been studied by means of the self\|consistent \%ab initio\% Hartree\|Fock and the second\|order Mφller\|Plesset correlation energy correction methods. The counterpoise procedure was used to check the basis set superposition error(BSSE) of the binding energies. There exist cyclic structures in a formamide dimer(Ⅰ),a HAN dimer(Ⅱ) and their heterodimer(Ⅲ). The corrected binding energies for dimers Ⅰ,Ⅱ and Ⅲ are respectively -45.53,-45.83 and -43.89 kJ/mol at the MP2/aug\|cc\|p VDZ//HF/\{aug\|cc\|p VDZ\} level. The change of the Gibbs free energies(Δ\%G\%) in the process of Ⅰ+Ⅱ→2Ⅲ was predicted to be -2.74 kJ/mol at 298.15 K. Dimer Ⅲ can be spontaneously produced in the mixture of formamide and HAN,which is in agreement with the experimental fact that most cyanohydrins are capable of interacting with dipeptide cyclo\|His\|Phe(CHP).展开更多
The ultrasonic speeds,u and viscosities,ηof the binary mixtures of methyl acrylate with benzene,toluene,o-xylene,m-xylene,p-xylene,and mesitylene over the whole mole fraction range were measured at six different temp...The ultrasonic speeds,u and viscosities,ηof the binary mixtures of methyl acrylate with benzene,toluene,o-xylene,m-xylene,p-xylene,and mesitylene over the whole mole fraction range were measured at six different temperatures and at atmospheric pressure.From the experimental data,the excess isentropic compressibility,κ_(s)^(E),excess ultrasonic speed,u^(E),excess molar isentropic compressibility,K_(s,m)^(E),excess specific impedance,Z^(E)and deviations in viscosity,Δηhave been calculated.The partial molar isentropic compressions,K_(s,m,1) and K_(s,m,2),and excess partial molar isentropic compressions,K_(s,m,1)^(-E) and K_(s,m,2)^(-E) over the whole composition range,partial molar isentropic compressions,K_(s,m,1)^(-)and K_(s,m,2)^(-),and excesspartial molar isentropic compressions,K_(s,m,1)^(-E) and K_(s,m,2)^(-E)of the components at infinite dilution have also been calculated.The results specified the existence of weak interactions between unlike molecules,and these interactions follow the order:benzene>toluene>p-xylene>m-xylene>o-xylene>mesityle ne.The magnitude of interactions was found to be dependent on the number and position of the methyl groups in these aromatic hydrocarbons.展开更多
The miscibility of the blend,composed of a bisphenol A epoxy resins (Diglycidyl ether of bisphenol A) (DGEBA) and poly(ethylene oxide) (PEG) and crosslinked by phthalic anhydride (PA) was studied using dynamic mechani...The miscibility of the blend,composed of a bisphenol A epoxy resins (Diglycidyl ether of bisphenol A) (DGEBA) and poly(ethylene oxide) (PEG) and crosslinked by phthalic anhydride (PA) was studied using dynamic mechanical method. Single glass transition temperatures intermediate between the two pure components were observed for all blend levels. The secondary relaxation mechanism should relate to not only diester linkage, but also hydroxyether structural unit in the system. Fourier transform infrared spectroscopy (FTIR) is applied to study the curing reaction and intermolecular specific interaction of the system. The results indicate the PEO participates the crosslinking reaction, accelerates the curing reaction and make the reaction more perfect. The shifts of the hydroxyl band and carbonyl band demonstrate the presence of the intermolecular interaction in the cured blend. Moreover, the molecular interaction between the side hydroxyl in the hydroxyether units and the ether bond in PEO macromolecules is stronger.展开更多
The organic solid-state lightemitting materials have attracted more and more attention owing to their promising applications in displays,lasers and optical communications.In contrast to isolated molecule,there are var...The organic solid-state lightemitting materials have attracted more and more attention owing to their promising applications in displays,lasers and optical communications.In contrast to isolated molecule,there are various weak intermolecular interactions in organic solids that sometimes have a large impact on the excited-state properties and energy dissipation pathways,resulting in strong fluorescence/phosphorescence.It is increasingly necessary to reveal the luminescence mechanism of organic solids.Here,we briefly review how intermolecular interactions induce strong normal fluorescence,thermally activate delayed fluorescence and room-temperature phosphorescence in organic solids by examining changes in geometry,electronic structures,electron-vibration coupling and energy dissipation dynamics of the excited states from isolated to aggregated molecules.We hope that the review will contribute to an in-depth understanding of the excited state properties of organic solids and to the design of excellent solid-state light-emitting materials.展开更多
Covalent bonds arise from the overlap of the electronic clouds in the internucleus region, which is a pure quantum effect and cannot be obtained in any classical way. If the intermolecular interaction is of covalent c...Covalent bonds arise from the overlap of the electronic clouds in the internucleus region, which is a pure quantum effect and cannot be obtained in any classical way. If the intermolecular interaction is of covalent character, the result from direct applications of classical simulation methods to the molecular system would be questionable. Here, we analyze the special intermolecular interaction between two NO molecules based on quantum chemical calculation. This weak intermolecular interaction, which is of covalent character, is responsible for the formation of the NO dimer,（NO）2, in its most stable conformation, a cis conformation. The natural bond orbital（NBO） analysis gives an intuitive illustration of the formation of the dimer bonding and antibonding orbitals concomitant with the breaking of the πbonds with bond order 0.5of the monomers. The dimer bonding is counteracted by partially filling the antibonding dimer orbital and the repulsion between those fully or nearly fully occupied nonbonding dimer orbitals that make the dimer binding rather weak. The direct molecular mechanics（MM） calculation with the UFF force fields predicts a trans conformation as the most stable state, which contradicts the result of quantum mechanics（QM）. The lesson from the investigation of this special system is that for the case where intermolecular interaction is of covalent character, a specific modification of the force fields of the molecular simulation method is necessary.展开更多
The intermolecular interaction in an azobenzene self-assembled monolayers (SAMs) on gold electrode was investigated by controlling the assembling time and using mixed self-assembled techniques, and the variation of ap...The intermolecular interaction in an azobenzene self-assembled monolayers (SAMs) on gold electrode was investigated by controlling the assembling time and using mixed self-assembled techniques, and the variation of apparent electron transfer rate constant (k(s)) of azobenzene SAMs with different molecular packing density is reported.展开更多
Geometries, interaction energies and electronic properties for four types of dimers（hydrogen bonded, halogen bonded, π-halogen bonded, and ~r-hydrogen bonded） between HCCF and HCCR（R=F, CI, Br） were studied via M...Geometries, interaction energies and electronic properties for four types of dimers（hydrogen bonded, halogen bonded, π-halogen bonded, and ~r-hydrogen bonded） between HCCF and HCCR（R=F, CI, Br） were studied via MP2/6-31 1＋＋G（d,p） ab initio calculation. It is shown that the strength of the zr-hydrogen bonded dimers turns out to be greater than those of the other three types of dimers, with the interaction energies --4.611 kJ/mol for HCCF-HCCF, -4.700 kJ/mol for HCCF-HCCC1, and -4.850 kJ/mol for HCCF-HCCBr respectively at the CCSD（T）/6-311＋＋ G（d,p）//MP2/6-31 1＋＋G（d,p） level. In an effort to understand the nature of the intermolecular interactions prevalent in these dimers, the interaction energies were decomposed into physically distinct energy components with the aid of the symmetry adapted perturbation theory（SAPT）. The dispersion force is found to be the main origin of the intermolecular interactions in hydrogen bonded and halogen bonded dimers. In the π-halogen bonded system, the dispersion is the major bonding force in HCCF-HCCF and HCCF-HCCC1, while the induction energy is the most important component in HCCF-HCCBr. However, both the dispersion and electrostatic energy play a key role in π-hydrogen bonded dimers.展开更多
Six fully optimized structures of the aza-calix[2]arene[2]-triazines/RDX supramo-lecular complexes have been obtained at the DFT-B3LYP/6-311＋＋G＊＊ level,and the corresponding intermolecular interactions have been i...Six fully optimized structures of the aza-calix[2]arene[2]-triazines/RDX supramo-lecular complexes have been obtained at the DFT-B3LYP/6-311＋＋G＊＊ level,and the corresponding intermolecular interactions have been investigated using the B3LYP,mPWPW91 and MP2 methods at the 6-311＋＋G＊＊ level,respectively.The natural bond orbital（NBO） and atoms in molecules（AIM） analyses have been performed to reveal the origin of interactions.To our interest,the result indicates that the strongest interaction is up to-22.34 kJ/mol after basis set superposition error（BSSE） and zero point energy（ZPE） correction at the MP2/6-311＋＋G＊＊ level.Furthermore,the intermolecular interactions between aza-calix[2]arene[2]-triazines with the substituted amidos and RDX are stronger than those of other complexes.Thus,the complexes with amidos can be used as the candidates to increase the stability of explosive and eliminate the explosive wastewater.展开更多
This work presents a study of intermolecular interactions using the model of the antigen antibody interactions of the ABO system. Absence of knowledge in the field of the ABO antigen’s behavior as a biomolecule and t...This work presents a study of intermolecular interactions using the model of the antigen antibody interactions of the ABO system. Absence of knowledge in the field of the ABO antigen’s behavior as a biomolecule and the integration of these structures into cascade of metabolic and physiological processes create the conditions, which promote a successful using this new model in the future. Molecular recognition and designing are included into the main catalog of computer methods of research, which is called “in silico”. Using PASS system, we describe the possible biological effects of pyruvate, lactate, antigen determinants A and B. Pharmacological effects and molecular mechanisms of influence on activity of the factors regulating inside and intercellular interactions are predicted for such minor components as pyruvate and lactate. Due to variety of the biological effects, glycoproteins A and B are very perspective to study as biological active connections. The obtained knowledge proves that AB0 antigens, as well as other glycoprotein conjugates are important mediators of intercellular adhesion and participants of signal transmission. Using ABO blood group system as a model helped to describe individual differences of parameters—degree and time of the agglutination beginning of antigen/antibody blood types of the AB0—are revealed.展开更多
Six fully optimized geometries of urea nitrate cation and RDX complexes have been obtained with DFT-B3LYP and MP2 methods at the 6-311＋＋G＊＊ level. The intermolecular interaction energies have been calculated with ...Six fully optimized geometries of urea nitrate cation and RDX complexes have been obtained with DFT-B3LYP and MP2 methods at the 6-311＋＋G＊＊ level. The intermolecular interaction energies have been calculated with basis set superposition error （BSSE） and zero point energy （ZPE） correction. The nature of intermolecular interaction has been revealed by the analysis of AIM and NBO. The results indicate that the greatest binding energy of urea nitrate with RDX is –82.47kJ/mol. The O–H…O and N–H…O hydrogen bonds are important intermolecular interactions of urea nitrate cation with RDX, and the origin of hydrogen bonds is the oxygen atom offering its lone-pair electrons to the σ（O-H）＊ or σ（O-H）＊ antibonding orbital. The intermolecular interactions strengthen the N–NO2 bond, leading to the reduced sensitivity of urea nitrate and RDX mixture explosive.展开更多
Ultralong organic phosphorescence(UOP)materials have received considerable attention in the field of organic optoelectronics due to their long lifetime,high exciton utilization,large Stokes shift,and so on.Great advan...Ultralong organic phosphorescence(UOP)materials have received considerable attention in the field of organic optoelectronics due to their long lifetime,high exciton utilization,large Stokes shift,and so on.Great advancements have been achieved through manipulating intermolecular interactions for high-performance UOP materials in recent years.This review will discuss the influence of various intermolecular interactions,includingπ-πinteractions,n-πinteractions,halogen bonding,hydrogen bonding,coordinative bonding,and ionic bonding on phosphorescent properties at room temperature,respectively.We summarize the rule of manipulating intermolecular interactions for UOP materials with superior phosphorescent properties.This review will provide a guideline for developing new UOP materials with superior phosphorescent properties for potential applications in organic electronics and bioelectronics.展开更多
Asymmetric nonfullerene acceptors(NFAs)possess larger dipole moments and stronger intermolecular bonding energy than their symmetric counterparts thereby making them promising candidates for high-performance polymer s...Asymmetric nonfullerene acceptors(NFAs)possess larger dipole moments and stronger intermolecular bonding energy than their symmetric counterparts thereby making them promising candidates for high-performance polymer solar cells(PSCs).Herein,we report twoefficient acceptor–donor–acceptor(A–D–A)type NFAs(M14 and M18)with asymmetric side chains that show enhanced intermolecular interactions compared with their corresponding counterparts(M17 and M19)based on symmetric side chains.Furthermore,M14 and M18 exhibit elevated lowest unoccupiedmolecular orbitals and smallerπ–πstacking distances in comparison with M17 and M19,respectively.In combination with the benchmark polymer donor of PM6,the PM6:M14 blend affords superior charge transport properties,and more importantly,an increased power conversion efficiency(PCE)of 15.49%in comparison with the M17-based counterpart(13.01%PCE).Similarly,the asymmetric M18-based blend also shows a higher PCE of 13.00%than the M19-based blend(11.55%).Through further interface engineering,the bestperforming M14-based device delivers an enhanced PCE of 16.46%,which represents a record value among all asymmetric A–D–A type NFAs.Our results provide new insights into the design of asymmetric NFAs with enhanced intermolecular interactions for highperformance PSCs.展开更多
基金support from the National Natural Science Foundation of China(Nos.52120105007,51834010)the National Science Fund for Distinguished Young Scholars(No.52222403).
文摘Fracturing fluid property play a critical role in developing unconventional reservoirs.Deep eutectic solvents(DESs)show fascinating potential for property improvement of clean fracturing fluids(CFFs)due to their low-price,low-toxicity,chemical stability and flexible designability.In this work,DESs were synthesized by mixing hydrogen bond acceptors(HBAs)and a given hydrogen bond donor(HBD)to explore their underlying influence on CFF properties based on the intermolecular interactions.The hydrogen-bonding,van der Waals and electrostatic interactions between DES components and surfactants improved the CFF properties by promoting the arrangement of surfactants at interface and enhancing the micelle network strength.The HBD enhanced the resistance of CFF for Ca^(2+) due to coordination-bonding interaction.The DESs composed of choline chloride(ChCl)and malonic acid show great enhancement for surface,rheology,temperature resistance,salt tolerance,drag reduction,and gel-breaking performance of CFFs.The DESs also improved the gel-breaking CFF-oil interactions,increasing the imbibition efficiencies to 44.2%in 74 h.Adjusting HBAs can effectively strengthen the intermolecular interactions(e.g.,HBA-surfactant and HBD-surfactant interactions)to improve CFF properties.The DESs developed in this study provide a novel strategy to intensify CFF properties.
基金This work is supported by the National Natural Science Foundation of China （No.21473171 and No.21573208）, the Pundamental Research Funds for the Central Universities （No.JB160508）, and the Huashan Mountain Scholar Program.
文摘Molecular self-assembly is extremely important in many fields, but the characterization of their corresponding intermolecular interactions is still lacking. The C-H stretching Raman band can reflect the hydrophobic interactions during the self-assembly process of sodium dodecyl sulfate （SDS） in aqueous solutions. However, the Raman spectra in this region are seriously overlapped by the OH stretching band of water. In this work, vertically polarized Raman spectra were used to improve the detection sensitivity of spectra of C-H region for the first time. The spectral results showed that the first critical micelle concentration and the second critical micelle concentration of SDS in water were 8.5 and 69 mmol/L, respectively, which were consistent with the results given by surface tension measurements. Because of the high sensitivity of vertically polarized Raman spectra, the critical micelle concentration of SDS in a relatively high concentration of salt solution could be obtained in our experiment. The two critical concentrations of SDS in 100 mmol/L NaCl solution were recorded to be 1.8 and 16.5 mmol/L, respectively. Through comparing the spectra and surface tension of SDS in water and in NaCl solution, the self-assembly process in bulk phase and at interface were discussed. The interactions among salt ions, SDS and water molecules were also analyzed. These results demonstrated the vertically polarized Raman spectra could be employed to study the self-assembly process of SDS in water.
基金financialy supported by the National Natural Science Foundation of China(51773071)the National 1000-Talents Program+2 种基金Innovation Fund of WNLOthe Fundamental Research Funds for the Central Universities(HUST:2017KFYXJJ023,2017KFXKJC002,2018KFYXKJC018,and 2019kfy RCPY099)Hubei Provincial Natural Science Foundation of China(2019CFA002)
文摘Organic batteries have attracted a lot of attention due to the advantages of flexibility,light weight,vast resources,low cost,recyclability,and ease to be functionalized through molecular design.The biggest difference between organic materials and inorganic materials is the relatively weak intermolecular interactions in organic materials but strong covalent or ionic bonds in inorganic materials,which is the inherent reason of their different physiochemical and electrochemical characteristics.Therefore,the relatively weak intermolecular interactions can indisputably affect the electrochemical performance of organic batteries significantly.Herein,the intermolecular interactions that are closely related to organic redox-active materials and unique in organic batteries are summarized into three parts:1)between neighbor active molecules,2)between active molecules and the conduction additives,and 3)between active molecules and the binders.We hope this short review can give a distinct viewpoint for better understanding the internal reasons of high-performance batteries and stimulate the deep studies of relatively weak intermolecular interactions for strengthening the performance of organic batteries.
文摘Intermolecular interactions and properties of TNT（2,4,6-trinitrotoluene）/CL-20（2,4,6,8,10,12-hexanitrohexaazaisowurtzitane） cocrystal were studied by density functional theory（DFT） methods. Binding energy, natural bond orbital（NBO）, and atom in molecules（AIM） analysis were performed to investigate the intermolecular interactions in the cocrystal. Results show that the unconventional CH···O type hydrogen bond plays a key role in forming the cocrystal. The variation tendency of entropy and enthalpy shows that the formation of the cocrystal is an exothermic process and low temperature will be benefit for the assembling of complexes. The calculated detonation velocity of the cocrystal agrees well with the experimental value which is higher than that of the physical mixture of TNT and CL-20. In addition, bond dissociation energies（BDEs） of the weakest trigger bond in TNT/CL-20 complex were calculated and the results show that the TNT/CL-20 complex is thermally stable. Finally, first-principles calculations were performed and analysis of the nitro group Mulliken charge indicates that the cocrystal is less sensitive than pure CL-20.
基金Supported by the National Natural Science Foundation of China(No.2 0 1730 2 8) and the Postdoctoral Foundation of theMinistry of Education of China
文摘Ab initio calculations at the B3LYP/3-21G^(**), HF/3-21G>^(**) and ONIOM(HF/3-21G^(**): AM1) levels of the theory in combination with counterpoise procedure for BSSE correction were performed on HMX dimers. There exist two O...H intermolecular contacts and the dispersion forces are dominant in the dimers. The corrected binding energies of the dimer are -15.10 and -17.81 kJ/mol at the HF/3-21G^(**) and \{ONIOM(HF/3-21G^(**): AM1) \}levels, respectively. The calculation by the B3LYP method gives irrational corrected binding energies though it produces similar intermolecular distances as those produced by the HF or \{ONIOM\} method. The geometrical parameters, the contact distances and the binding energies demonstrated, for the first time, the validity of the ONIOM method applied in the calculation of the parameters of intermolecular interactions.
文摘Five fully optimized structures of complexes between aza-calix[6]arene host monomers（Ma～Me） and complexes（a～e） have been obtained at the B3LYP/6-31G（d） level.Natural bond orbital（NBO） analysis was performed to reveal the origin of the interaction.The intermolecular interaction energy was evaluated with basis set superposition error correction（BSSE） and zero point energy correction（ZPEC）.The B3LYP/6-31G（d） calculations on the five complexes have shown that the greatest interaction（–13.98 kJ/mol） is found in the complex between HMX and hexa-aza-calix[3]-p-tri-arene[3]-2-amido-1,3,5-tri-azine.The results have indicated that intermolecular interaction energies of aza-calix[6]arenes with substituted group are stronger than those without substituted group,and those with amido are greater than with nitryl.Thus,hexa-azacalix[3]-p-tri-arene[3]-2-amido-1,3,5-tri-azine is rather equal to eliminate HMX from explosive waste water.
文摘Tetrazole monomers （Ⅰ, Ⅱ） and all of their possible stable dimers （1, 2, 3, 4, 5, 6, 7 and 8） were fully optimized by DFT method at the B3LYP/6-311＋＋G^＊＊ level. Among the eight dimers, there were two 1H-tetrazole dimers, three 2H-tetrazole dimers and three hetero dimers of 1H-tetrazole and 2H-tetrazole. Vibrational frequencies were calculated to ascertain that each structure was stable （no imaginary frequencies）. The basis set superposition errors （BSSE） are 2.78, 2.28, 2.97, 2.75, 2.74, 2.18, 1.23 and 3.10 kJ/mol, and the zero point energy （ZPE） corrections for the interaction energies are 4.88, 4.18, 3.87, 3.65, 3.54, 3.22, 2.87 and 4.34 kJ/mol for 1, 2, 3, 4, 5, 6, 7 and 8, respectively. After BSSE and ZPE corrections, the greatest corrected intermolecular interaction energy of the dimers is -43.71 kJ/mol. The charge redistribution mainly occurs on the adjacent N-H…N atoms between submolecules. The charge transfer between two subsystems is very small. Natural bond orbital （NBO） analysis was performed to reveal the origin of the interaction. Based on the statistical thermodynamic method, the standard thermodynamic functions, heat capacities （C^0P）, entropies （S^0T） and thermal corrections to enthalpy （H^0T）, and the changes of thermodynamic properties from monomer to dimer in the temperature range of 200.00 K to 700 K have been obtained. 1H-tetrazole monomer can spontaneously turn into two stable dimers at 298.15 K.
基金Project of National Natural Science Foundation of China (No. 10576030, 20173028)
文摘Seven optimized configurations and their electronic structures of 4-amino-5-nitro- 1,2,3-triazole dimers on their potential energy surface have been obtained by using density functional theory （DPT） method at the B3LYP/6-311＋＋G＊＊ level. The maximum intermolecular interaction energy is -35.42 kJ/mol via the basis set superposition error-correction （BSSE） and zero point energy-correction （ZPE）. Charge transfers between the two subsystems are small. The vibration analysis of optimized configurations was performed, and the thermodynamic property changes from monomer to dimer have been obtained with the temperature ranging from 200 to 800 K on the basis of statistical thermodynamics. It is found that the hydrogen bonds contribute to the dimers dominantly, and the extent of intermolecular interaction is mainly determined by the hydrogen bonds＇ strength rather than their number. The dimerization processes of Ⅳ, Ⅴand Ⅵ can occur spontaneously at 200 K.
文摘The structures,the binding energies and the thermodynamic properties of formamide and hydroxyacetonitrile(HAN) dimers have been studied by means of the self\|consistent \%ab initio\% Hartree\|Fock and the second\|order Mφller\|Plesset correlation energy correction methods. The counterpoise procedure was used to check the basis set superposition error(BSSE) of the binding energies. There exist cyclic structures in a formamide dimer(Ⅰ),a HAN dimer(Ⅱ) and their heterodimer(Ⅲ). The corrected binding energies for dimers Ⅰ,Ⅱ and Ⅲ are respectively -45.53,-45.83 and -43.89 kJ/mol at the MP2/aug\|cc\|p VDZ//HF/\{aug\|cc\|p VDZ\} level. The change of the Gibbs free energies(Δ\%G\%) in the process of Ⅰ+Ⅱ→2Ⅲ was predicted to be -2.74 kJ/mol at 298.15 K. Dimer Ⅲ can be spontaneously produced in the mixture of formamide and HAN,which is in agreement with the experimental fact that most cyanohydrins are capable of interacting with dipeptide cyclo\|His\|Phe(CHP).
文摘The ultrasonic speeds,u and viscosities,ηof the binary mixtures of methyl acrylate with benzene,toluene,o-xylene,m-xylene,p-xylene,and mesitylene over the whole mole fraction range were measured at six different temperatures and at atmospheric pressure.From the experimental data,the excess isentropic compressibility,κ_(s)^(E),excess ultrasonic speed,u^(E),excess molar isentropic compressibility,K_(s,m)^(E),excess specific impedance,Z^(E)and deviations in viscosity,Δηhave been calculated.The partial molar isentropic compressions,K_(s,m,1) and K_(s,m,2),and excess partial molar isentropic compressions,K_(s,m,1)^(-E) and K_(s,m,2)^(-E) over the whole composition range,partial molar isentropic compressions,K_(s,m,1)^(-)and K_(s,m,2)^(-),and excesspartial molar isentropic compressions,K_(s,m,1)^(-E) and K_(s,m,2)^(-E)of the components at infinite dilution have also been calculated.The results specified the existence of weak interactions between unlike molecules,and these interactions follow the order:benzene>toluene>p-xylene>m-xylene>o-xylene>mesityle ne.The magnitude of interactions was found to be dependent on the number and position of the methyl groups in these aromatic hydrocarbons.
基金This study is partially supported by the National Natural Science Foundation of China.
文摘The miscibility of the blend,composed of a bisphenol A epoxy resins (Diglycidyl ether of bisphenol A) (DGEBA) and poly(ethylene oxide) (PEG) and crosslinked by phthalic anhydride (PA) was studied using dynamic mechanical method. Single glass transition temperatures intermediate between the two pure components were observed for all blend levels. The secondary relaxation mechanism should relate to not only diester linkage, but also hydroxyether structural unit in the system. Fourier transform infrared spectroscopy (FTIR) is applied to study the curing reaction and intermolecular specific interaction of the system. The results indicate the PEO participates the crosslinking reaction, accelerates the curing reaction and make the reaction more perfect. The shifts of the hydroxyl band and carbonyl band demonstrate the presence of the intermolecular interaction in the cured blend. Moreover, the molecular interaction between the side hydroxyl in the hydroxyether units and the ether bond in PEO macromolecules is stronger.
基金supported by the National Natural Science Foundation of China(No.21973099)。
文摘The organic solid-state lightemitting materials have attracted more and more attention owing to their promising applications in displays,lasers and optical communications.In contrast to isolated molecule,there are various weak intermolecular interactions in organic solids that sometimes have a large impact on the excited-state properties and energy dissipation pathways,resulting in strong fluorescence/phosphorescence.It is increasingly necessary to reveal the luminescence mechanism of organic solids.Here,we briefly review how intermolecular interactions induce strong normal fluorescence,thermally activate delayed fluorescence and room-temperature phosphorescence in organic solids by examining changes in geometry,electronic structures,electron-vibration coupling and energy dissipation dynamics of the excited states from isolated to aggregated molecules.We hope that the review will contribute to an in-depth understanding of the excited state properties of organic solids and to the design of excellent solid-state light-emitting materials.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.90403007 and 10975044)the Key Subject Construction Project of Hebei Provincial Universities,China+2 种基金the Research Project of Hebei Education Department,China(Grant Nos.Z2012067 and Z2011133)the National Natural Science Foundation of China(Grant No.11147103)the Open Project Program of State Key Laboratory of Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of Sciences,China(Grant No.Y5KF211CJ1)
文摘Covalent bonds arise from the overlap of the electronic clouds in the internucleus region, which is a pure quantum effect and cannot be obtained in any classical way. If the intermolecular interaction is of covalent character, the result from direct applications of classical simulation methods to the molecular system would be questionable. Here, we analyze the special intermolecular interaction between two NO molecules based on quantum chemical calculation. This weak intermolecular interaction, which is of covalent character, is responsible for the formation of the NO dimer,（NO）2, in its most stable conformation, a cis conformation. The natural bond orbital（NBO） analysis gives an intuitive illustration of the formation of the dimer bonding and antibonding orbitals concomitant with the breaking of the πbonds with bond order 0.5of the monomers. The dimer bonding is counteracted by partially filling the antibonding dimer orbital and the repulsion between those fully or nearly fully occupied nonbonding dimer orbitals that make the dimer binding rather weak. The direct molecular mechanics（MM） calculation with the UFF force fields predicts a trans conformation as the most stable state, which contradicts the result of quantum mechanics（QM）. The lesson from the investigation of this special system is that for the case where intermolecular interaction is of covalent character, a specific modification of the force fields of the molecular simulation method is necessary.
文摘The intermolecular interaction in an azobenzene self-assembled monolayers (SAMs) on gold electrode was investigated by controlling the assembling time and using mixed self-assembled techniques, and the variation of apparent electron transfer rate constant (k(s)) of azobenzene SAMs with different molecular packing density is reported.
基金Supported by the Scientific Research Fund of Hunan Provincial Education Department(No.B30865)Research Foundation of Hunan University of Science and Technology,China(No.E50814)
文摘Geometries, interaction energies and electronic properties for four types of dimers（hydrogen bonded, halogen bonded, π-halogen bonded, and ~r-hydrogen bonded） between HCCF and HCCR（R=F, CI, Br） were studied via MP2/6-31 1＋＋G（d,p） ab initio calculation. It is shown that the strength of the zr-hydrogen bonded dimers turns out to be greater than those of the other three types of dimers, with the interaction energies --4.611 kJ/mol for HCCF-HCCF, -4.700 kJ/mol for HCCF-HCCC1, and -4.850 kJ/mol for HCCF-HCCBr respectively at the CCSD（T）/6-311＋＋ G（d,p）//MP2/6-31 1＋＋G（d,p） level. In an effort to understand the nature of the intermolecular interactions prevalent in these dimers, the interaction energies were decomposed into physically distinct energy components with the aid of the symmetry adapted perturbation theory（SAPT）. The dispersion force is found to be the main origin of the intermolecular interactions in hydrogen bonded and halogen bonded dimers. In the π-halogen bonded system, the dispersion is the major bonding force in HCCF-HCCF and HCCF-HCCC1, while the induction energy is the most important component in HCCF-HCCBr. However, both the dispersion and electrostatic energy play a key role in π-hydrogen bonded dimers.
文摘Six fully optimized structures of the aza-calix[2]arene[2]-triazines/RDX supramo-lecular complexes have been obtained at the DFT-B3LYP/6-311＋＋G＊＊ level,and the corresponding intermolecular interactions have been investigated using the B3LYP,mPWPW91 and MP2 methods at the 6-311＋＋G＊＊ level,respectively.The natural bond orbital（NBO） and atoms in molecules（AIM） analyses have been performed to reveal the origin of interactions.To our interest,the result indicates that the strongest interaction is up to-22.34 kJ/mol after basis set superposition error（BSSE） and zero point energy（ZPE） correction at the MP2/6-311＋＋G＊＊ level.Furthermore,the intermolecular interactions between aza-calix[2]arene[2]-triazines with the substituted amidos and RDX are stronger than those of other complexes.Thus,the complexes with amidos can be used as the candidates to increase the stability of explosive and eliminate the explosive wastewater.
文摘This work presents a study of intermolecular interactions using the model of the antigen antibody interactions of the ABO system. Absence of knowledge in the field of the ABO antigen’s behavior as a biomolecule and the integration of these structures into cascade of metabolic and physiological processes create the conditions, which promote a successful using this new model in the future. Molecular recognition and designing are included into the main catalog of computer methods of research, which is called “in silico”. Using PASS system, we describe the possible biological effects of pyruvate, lactate, antigen determinants A and B. Pharmacological effects and molecular mechanisms of influence on activity of the factors regulating inside and intercellular interactions are predicted for such minor components as pyruvate and lactate. Due to variety of the biological effects, glycoproteins A and B are very perspective to study as biological active connections. The obtained knowledge proves that AB0 antigens, as well as other glycoprotein conjugates are important mediators of intercellular adhesion and participants of signal transmission. Using ABO blood group system as a model helped to describe individual differences of parameters—degree and time of the agglutination beginning of antigen/antibody blood types of the AB0—are revealed.
文摘Six fully optimized geometries of urea nitrate cation and RDX complexes have been obtained with DFT-B3LYP and MP2 methods at the 6-311＋＋G＊＊ level. The intermolecular interaction energies have been calculated with basis set superposition error （BSSE） and zero point energy （ZPE） correction. The nature of intermolecular interaction has been revealed by the analysis of AIM and NBO. The results indicate that the greatest binding energy of urea nitrate with RDX is –82.47kJ/mol. The O–H…O and N–H…O hydrogen bonds are important intermolecular interactions of urea nitrate cation with RDX, and the origin of hydrogen bonds is the oxygen atom offering its lone-pair electrons to the σ（O-H）＊ or σ（O-H）＊ antibonding orbital. The intermolecular interactions strengthen the N–NO2 bond, leading to the reduced sensitivity of urea nitrate and RDX mixture explosive.
基金National Natural Science Foundation of China,Grant/Award Numbers:22105038,21912750Fujian Province Natural Science Foundation of China,Grant/Award Number:2022J01654Fujian Normal University Start-up Grant,Grant/Award Number:Y0720306K13。
文摘Ultralong organic phosphorescence(UOP)materials have received considerable attention in the field of organic optoelectronics due to their long lifetime,high exciton utilization,large Stokes shift,and so on.Great advancements have been achieved through manipulating intermolecular interactions for high-performance UOP materials in recent years.This review will discuss the influence of various intermolecular interactions,includingπ-πinteractions,n-πinteractions,halogen bonding,hydrogen bonding,coordinative bonding,and ionic bonding on phosphorescent properties at room temperature,respectively.We summarize the rule of manipulating intermolecular interactions for UOP materials with superior phosphorescent properties.This review will provide a guideline for developing new UOP materials with superior phosphorescent properties for potential applications in organic electronics and bioelectronics.
基金supported by the National Natural Science Foundation of China(nos.22101285,51873138,52130306,21734009,and 22075287)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(CAS)(no.QYZDB-SSW-SLH032)+2 种基金the China Postdoctoral Science Foundation(no.2021M703218)the Program of Youth Innovation Promotion Association CAS(no.2021000060)Beijing National Laboratory for Molecular Sciences(no.BNLMS201902).
文摘Asymmetric nonfullerene acceptors(NFAs)possess larger dipole moments and stronger intermolecular bonding energy than their symmetric counterparts thereby making them promising candidates for high-performance polymer solar cells(PSCs).Herein,we report twoefficient acceptor–donor–acceptor(A–D–A)type NFAs(M14 and M18)with asymmetric side chains that show enhanced intermolecular interactions compared with their corresponding counterparts(M17 and M19)based on symmetric side chains.Furthermore,M14 and M18 exhibit elevated lowest unoccupiedmolecular orbitals and smallerπ–πstacking distances in comparison with M17 and M19,respectively.In combination with the benchmark polymer donor of PM6,the PM6:M14 blend affords superior charge transport properties,and more importantly,an increased power conversion efficiency(PCE)of 15.49%in comparison with the M17-based counterpart(13.01%PCE).Similarly,the asymmetric M18-based blend also shows a higher PCE of 13.00%than the M19-based blend(11.55%).Through further interface engineering,the bestperforming M14-based device delivers an enhanced PCE of 16.46%,which represents a record value among all asymmetric A–D–A type NFAs.Our results provide new insights into the design of asymmetric NFAs with enhanced intermolecular interactions for highperformance PSCs.
