Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1237716 | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy | 2008 | 6 Pages |
Abstract
Eleven possible conformers of glycylglycine have been studied by using the BLYP, B3LYP methods of density functional theory and the HF method at the basis set of 6-311++G**. BLYP (using Becke's and Lee-Yang-Parr's correlation functionals), ab initio Hartree-Fock (HF) and hybrid DFT/HF B3LYP calculations have been carried out to study the structure and vibrational spectra of glycylglycine. Glycylglycine crystal structure has been determined by X-ray diffraction analysis. The title compound has been crystallizes in the orthorhombic space group C1, with Z = 4. And the unit cell parameters are: a = 8.1184(12) Ã
, b = 9.5542(14) Ã
, c = 7.8192(11) Ã
and VÂ =Â 577.95(15)Â Ã
3. Molecular conformation calculations have got 11 possible conformers. In these possible conformers, the most stable one has been selected. The BLYP/6-311++G** and scaled HF/6-311++G** frequencies correspond well with available experimental assignments of the normal vibrational modes. Comparison of the observed fundamental vibrational frequencies of glycylglycine and calculated results by density functional B3LYP and Hartree-Fock (HF) methods indicates that B3LYP is superior to the scaled Hartree-Fock (HF) for molecular vibrational issues.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Bin Zhao, Chun Wang, Shulei Zhao, Mei Qin, Zhengyu Zhou, Yuxi Sun,