Electrical influence on molecular conformation in glyoxal and glycine

Abstract

Ab initio calculations have been performed to find the internal rotation potentials of glyoxal and glycine under the influence of different external electric fields and electric field gradients. Not only is the interconversion barrier height directly affected by both fields and field gradients, but also important is the reshaping of the internal rotational potentials. In certain regions, a field gradient introduces a particularly sharp dependence of the potential on the internal rotation angle. These results serve to give a quantitative assessment of the field and field gradient strengths necessary for influencing conformational energetics and dynamics. We also find that there is mostly a small interplay between electron correlation effects and the conformational effects of the electric field and field gradient, including those from sizable fields and field gradients.