AN AB-INITIO STUDY OF PYRUVIC-ACID

The geometries and vibrational frequencies of two conformers of pyruvi c acid have been obtained at the ab initio second order Moller-Plesset level of theory using the 6-311++G* basis set. While the calculated geometries have been compared to the experimental microwave data, the vibrational frequencies have been assigned, using the experimental gas phase IR spectra of 13 isotopes of pyruvic acid by a recently develop ed scaling procedure (IRPROG). An attempt has been made to explain the stability of the eclipsed conformation over the staggered conformatio n of pyruvic acid by taking account of the molecular orbitals. (C) 199 8 Elsevier Science B.V.