What are the spectroscopic properties of HFC-32? Answers from DFT

摘要: Although coupled cluster theory to large basis sets can reach impressive accuracies for thermochemical and spectroscopic properties, it is still limited small/medium sized molecules. Density functional (DFT) represents the working option systems composed of hundreds thousands heavy atoms. In this context, investigations are required aimed at characterizing performances different density functionals (DF). This work focuses on study DFT in prediction with particular attention vibrational problem, by focusing CH2F2 molecule as a test case. An extensive systematic investigation performed several model chemistries testing their predictions molecular constants frequencies intensities against CCSD(T)/aug-cc-pCVQZ data. B3LYP, B3PW91, B97-1, PBE0, TPSSh, M05, M05-2X, B2PLYP DFs used conjunction variety sets. Anharmonic derived from VPT2 treatment anharmonic- hybrid CCSD(T)/DFT-force fields. A software computations also presented. © 2014 Wiley Periodicals, Inc.