Structural and energetic properties of α-amino acids: a first principles density functional study

Abstract

The structures, energetics and ionisation potentials of the 20 standard α-amino acids, in both neutral and positively charged states, are investigated using density functional theory by using the Becke–Lee–Yang–Parr (BLYP) generalised gradient corrections to the local density approximation exchange and correlation energy, norm-conserving pseudopotentials, and a plane-wave expansion of Kohn–Sham orbitals. There is a good agreement between our theory and the available experiments, increasing the confidence in density functional theoretical descriptions of this important class of bio-molecules.

Keywords:

• bio-molecules
• density functional theory
• amino acids
• optimisation

Acknowledgements

S. Kishor acknowledges the support of the Indian Academy of Sciences, the Indian National Science Academy and the National Academy of Sciences, for the Summer Research Fellowship Programme, which enabled him to spend the summer of 2007 at B.A.R.C., Mumbai, during which this work was conceptualised. This work was possible due to the facilities, and help from the staff, of the BARC computer centre.