Portal de Periódicos da CAPES

Use of ab initio computational results and experimental frequencies to construct the internal rotational potential function for acrolein

1987; Elsevier BV; Volume: 160; Issue: 3-4 Linguagem: Inglês

10.1016/0022-2860(87)80073-x

1872-8014

George R. De Maré, Yu. N. Panchenko, А.В. Абраменков,

Spectroscopy and Quantum Chemical Studies

Ab initio optimizations of the complete acrolein molecular geometry accomplished using analytical gradient methods at the 6-31G* SCF level at ten points during rotation from the planar trans- to the planar cis-form (rotation about the single CC bond) are used to calculate the values of the Pitzer function F(φ), the coefficients of its Fourier expansion, and the coefficients in the potential energy expansion. The theoretical potential expansion coefficients are then adjusted using the experimental torsional frequencies and their overtones for the trans- and cis-forms of CH2CHCHO and CH2CHCDO. For the cis-conformer two different sets of experimental frequencies are employed. The dependence of the slope of the acrolein potential energy curve on the experimental frequency set used for the cis-rotamer is discussed.