Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be ...Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be strictly controlled.The bond length,bond angle,energy,dipole moment,orbital energy level distribution of dioxin under the external field are investigated using DFT(density functional theory)on basis set level of B3LYP/6-31G(d,p).The results indicate that with the increase of the electric field,the length of one Carbon-Oxygen bond increases while another Carbon-Oxygen bond decreases.The energy gradually decreases with the electric field,while the change of the dipole moment has an opposite trend.In the infrared spectra,the vibration frequency decreases with the electric field increasing and shows an obvious red shift.Moreover,the ultraviolet-visible absorption spectra under different electric fields are analyzed with TD-DFT(time-dependent density functional theory)method.The wavelength of the strongest absorption peak increases and occurs red shift with the increase of the electric field.All the above results can provide reference for further research on the properties of dioxin under different external electric field.展开更多
Oxalyl chloride is a highly toxic and caustic substance, which widely exists in human production and life as a kind of volatile organic compound. Based on the density functional theory B3 LYP at 6-311++G(d, p) level, ...Oxalyl chloride is a highly toxic and caustic substance, which widely exists in human production and life as a kind of volatile organic compound. Based on the density functional theory B3 LYP at 6-311++G(d, p) level, the influences of external electric field on the bond length, bond energy, dipole moment and dissociation mechanism are optimized. The results indicate that the C_1–Cl_3 bond length increases while the C_4–Cl_6 bond decreases. At the same time, the carbon-carbon bond length gradually increases with the increase of electric field. The total energy decreases while the dipole moment gradually increases with the increase of electric field. In the infrared spectra, the vibration frequency of the carbon-chlorine(C_4–Cl_6) bond decreases while the vibration frequency of the carbon-oxygen bond increases. In the ultraviolet-visible spectra, the wavelength of the strongest absorption peak increases as the external electric field increases and shows an observable red shift phenomenon. Additionally, single point energies of oxalyl chloride along the carbon-carbon bond are scanned with the equation-of-motion coupled cluster method restricted to single and double excitations(EOM-CCSD) method and the potential energy curves under different external electric fields are obtained. The dissociation barrier in potential energy curve decreases because of the breakage of carbon-carbon bond with the increase of external electric field. These results provide reference for further researches on the properties of oxalyl chloride and offer a theoretical basis for the study of oxalyl chloride degradation.展开更多
The ultrafast photodissociation dynamics of thionyl chloride after excitation with a 235 nm pump pulse has been studied using a femtosecond time-resolved mass spectroscopy.The observed parent transient suggests that t...The ultrafast photodissociation dynamics of thionyl chloride after excitation with a 235 nm pump pulse has been studied using a femtosecond time-resolved mass spectroscopy.The observed parent transient suggests that the excited states initiated by 235 nm are very shortlived,that is,approximately 166 fs.Not only a stepwise three-body dissociation pathway but also a concerted three-body dissociation pathway is observed.展开更多
Phosgene is highly toxic, and it plays a role in the depletion of the ozone layer. The ground state geometric structure and spectral characteristic of phosgene in various external electric fields were calculated via t...Phosgene is highly toxic, and it plays a role in the depletion of the ozone layer. The ground state geometric structure and spectral characteristic of phosgene in various external electric fields were calculated via the density-functional theory (DFT) and time-dependent density-functional theory (TDDFT) with the B3LYP/6-31+G(d) basis set. With external electric field, the structure of phosgene changed significantly. With increasing electric field, the bond lengths of 1C-3Cl and 1C-4Cl increased;the total energy and energy gap initially increased and then decreased, whereas the dipole moment initially decreased and then increased. Most of the IR vibrational frequencies were redshifted. The wavelength of the singlet excited state increased, reflecting a red shift, and the oscillator strengths of most transitions belonged to forbidden transitions. These results are of great significance for studying the dissociation of phosgene in external electric field.展开更多
基金The project is supported by Natural Science Foundation of Xinjiang(No.2017D01B36).
文摘Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be strictly controlled.The bond length,bond angle,energy,dipole moment,orbital energy level distribution of dioxin under the external field are investigated using DFT(density functional theory)on basis set level of B3LYP/6-31G(d,p).The results indicate that with the increase of the electric field,the length of one Carbon-Oxygen bond increases while another Carbon-Oxygen bond decreases.The energy gradually decreases with the electric field,while the change of the dipole moment has an opposite trend.In the infrared spectra,the vibration frequency decreases with the electric field increasing and shows an obvious red shift.Moreover,the ultraviolet-visible absorption spectra under different electric fields are analyzed with TD-DFT(time-dependent density functional theory)method.The wavelength of the strongest absorption peak increases and occurs red shift with the increase of the electric field.All the above results can provide reference for further research on the properties of dioxin under different external electric field.
基金This project was supported by the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province of China(No.18KJA140002)National Natural Science Foundation of China(Nos.11564040,21763027)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX18_1015)Undergraduate Training Program for Innovation and Entrepreneurship(Nos.201710762008,201710762055)
文摘Oxalyl chloride is a highly toxic and caustic substance, which widely exists in human production and life as a kind of volatile organic compound. Based on the density functional theory B3 LYP at 6-311++G(d, p) level, the influences of external electric field on the bond length, bond energy, dipole moment and dissociation mechanism are optimized. The results indicate that the C_1–Cl_3 bond length increases while the C_4–Cl_6 bond decreases. At the same time, the carbon-carbon bond length gradually increases with the increase of electric field. The total energy decreases while the dipole moment gradually increases with the increase of electric field. In the infrared spectra, the vibration frequency of the carbon-chlorine(C_4–Cl_6) bond decreases while the vibration frequency of the carbon-oxygen bond increases. In the ultraviolet-visible spectra, the wavelength of the strongest absorption peak increases as the external electric field increases and shows an observable red shift phenomenon. Additionally, single point energies of oxalyl chloride along the carbon-carbon bond are scanned with the equation-of-motion coupled cluster method restricted to single and double excitations(EOM-CCSD) method and the potential energy curves under different external electric fields are obtained. The dissociation barrier in potential energy curve decreases because of the breakage of carbon-carbon bond with the increase of external electric field. These results provide reference for further researches on the properties of oxalyl chloride and offer a theoretical basis for the study of oxalyl chloride degradation.
基金This work was supported by the National Natural Science Foundation of China(No.11564040,No.21763027,No.11204264,No.11464045),the Natural Science Foundation of Xinjiang(No.2017D01B36),“13th Five-Year”Plan for Key Discipline Physics Bidding Project(No.17SDKD0602),Xinjiang Normal University and Science Foundation for Doctorate Research of Xinjiang Normal University(XJNUBS1511,XJNUBS1408),Teaching research and reform program of Xinjiang Normal University(No:SDJG2016C8).
文摘The ultrafast photodissociation dynamics of thionyl chloride after excitation with a 235 nm pump pulse has been studied using a femtosecond time-resolved mass spectroscopy.The observed parent transient suggests that the excited states initiated by 235 nm are very shortlived,that is,approximately 166 fs.Not only a stepwise three-body dissociation pathway but also a concerted three-body dissociation pathway is observed.
基金National Natural Science Foundation of China(Grant Number:21763027)Innovation Team for Monitoring of Emerging Contaminants and Biomarkers(Grant Number:2021D14017)+2 种基金Xinjiang Regional Collaborative Innovation Project(Grant Number:2019E0223)Scientific Research Program of Colleges and Universities in Xinjiang(Grant Number:XJEDU2020Y029)“13th Five-Year”Plan for Key Discipline Physics Bidding Project of Xinjiang Normal University(Grant Number:17SDKD0602).
文摘Phosgene is highly toxic, and it plays a role in the depletion of the ozone layer. The ground state geometric structure and spectral characteristic of phosgene in various external electric fields were calculated via the density-functional theory (DFT) and time-dependent density-functional theory (TDDFT) with the B3LYP/6-31+G(d) basis set. With external electric field, the structure of phosgene changed significantly. With increasing electric field, the bond lengths of 1C-3Cl and 1C-4Cl increased;the total energy and energy gap initially increased and then decreased, whereas the dipole moment initially decreased and then increased. Most of the IR vibrational frequencies were redshifted. The wavelength of the singlet excited state increased, reflecting a red shift, and the oscillator strengths of most transitions belonged to forbidden transitions. These results are of great significance for studying the dissociation of phosgene in external electric field.
