An ab-initio study of multiple conformers of glycine

Abstract

The recent combination of new computational chemistry techniques and high performance computational hardware is allowing unprecedented levels of accuracy in the calculations of physical quantities such as potential energy surfaces and rotational-vibrational spectra. Previous results exist in the literature for the first three most stable conformers of glycine at the aug-cc-pVDZ basis set. In this work, we extend the known results, presenting calculations of the four most stable conformers of glycine using the aug-cc-pVQZ basis set. We compare our calculations to experimental values and show that our current calculations differ by <2% from measured values, much better than results from previous years. When searching for molecules in the Interstellar Medium this small difference suggests that computational methods are becoming well-suited for the task. The natural question to ask is: at what point will the small deviation from experimental values render our computations just as reliable as experiments? We feel that the current results show that we are indeed close to this goal. © 2008 International Astronomical Union.