@article{article_379540, title={Detemination of The Best Method (HF, MP2 and B3LYP) in Calculation of Chemical Hardness}, journal={Turkish Computational and Theoretical Chemistry}, volume={2}, pages={7–15}, year={2018}, DOI={10.33435/tcandtc.379540}, author={Zaim, Zinet and Alagöz Sayın, Tuba and Sayın, Koray and Karakaş, Duran}, keywords={Molecular Orbital Energy,Chemical Hardness,HF,B3LYP,MP2}, abstract={<span lang="en-us" style="font-size:12pt;line-height:107%;font-family:’Times New Roman’, serif;" xml:lang="en-us">Chemical hardness of 62 molecules are calculated at different 18  levels. No imaginary frequency is observed in optimization results for each level. Correlation between experimental and calculated hardness values are investigated. To analyze this investigation, correlation coefficient and scale factor are calculated for each level. As a result, HF method is better in the calculation of chemical hardness and molecular orbital energy than B3LYP and MP2 methods. </span>}, number={2}, publisher={Koray SAYIN}