Scheme 1. The molecular graphs of glycine (left panel) with arrows indicating the directions of the positive electric (+)E -field of the C1-H3 BCP bond-path and C1-H10BCP bond-path. The unlabeled green spheres indicate the bond critical points (BCP s). The Sa and Ra stereoisomers (right panel) are defined for alignment of the (+)E -field along each of the C1-H3 BCP bond-path and C1-H10 BCP bond-path respectively.
E -fields are known to alter a PES in general[40]–[46]. In extraterrestrial regions, several molecular and ionic species in excited states generated by a strong electric field which can polarize chirality have been observed[47]. Recently, some of the current authors applied a directional (±)E -field on the ethene molecule and demonstrated atomic polarization of the shifted C-C and C-H bond critical points (BCPs )[48] . The recent Perspective by Shaiket al . considers the prospects of oriented external-electric-fields (OEEF), and other electric-field types, as ‘smart reagents’, for the control of reactivity and structure for chemical catalysis[49].
We will investigate the applicability of the stress tensor trajectory Tσ(s ) formalism as a molecular similarity measure by determination of any proportionate response to the application of anE -field to formally achiral glycine. The creation of enantiomers using formally achiral glycine enables the use of lowerE -fields, resulting in less structural distortion, to manipulate the S and R chirality than would be the case with chiral compounds. We will use a wide range of E -fields from ±20x10-4 a.u. to ±200x10-4 a.u., ≈ ±1.1x109 Vm-1 to 11 x109 Vm-1, which includesE -fields that are easily accessible experimentally, for example within a Scanning Tunneling Microscope (STM).