摘要
It is interesting to maximize the amount of information we can obtain from one experiment on a single sample. In obtaining all the thermodynamic properties of some materials from their experimental heat capacity data only, we aim to get the tempera- ture-independent energy spectrum. However, all the practical measured energy spectra depend on the temperature of experi- ments. One promising method to obtain the temperature-independent energy spectrum is to solve the so-called specific heat-phonon spectrum inversion （SPI） problem. Here we show, by developing a new practical solution method of SPI, the phonon spectrum of the negative thermal expansion material ZrW208 is obtained. This phonon spectrum is tempera- ture-independent and almost method independent. Hence all the thermodynamic properties of ZrW208, such as thermodynamic potential, entropy, Helmholtz free energy, etc. are obtained by heat capacity only.
It is interesting to maximize the amount of information we can obtain from one experiment on a single sample.In obtaining all the thermodynamic properties of some materials from their experimental heat capacity data only,we aim to get the temperature-independent energy spectrum.However,all the practical measured energy spectra depend on the temperature of experiments.One promising method to obtain the temperature-independent energy spectrum is to solve the so-called specific heat-phonon spectrum inversion(SPI) problem.Here we show,by developing a new practical solution method of SPI,the phonon spectrum of the negative thermal expansion material ZrW 2 O 8 is obtained.This phonon spectrum is temperature-independent and almost method independent.Hence all the thermodynamic properties of ZrW 2 O 8,such as thermodynamic potential,entropy,Helmholtz free energy,etc.are obtained by heat capacity only.
基金
supported by the National Natural Science Foundation of China (Grant Nos. 10675031,10375012 and 19975009)
the Department of Education of Zhejiang Province (Grant No. Y200906911)
