A computational study of the rotation barriers on C-N bond in formamide and its chalcogen substituents
Abstract
The determination of the origin of rotation barriers about C-N bond, in formamide and chalcogen substituent, showed a change in the carbon interaction site. However, in computational study, the origin of rotational barrier and the effect of substituting oxygen by chalcogen analogues were not well understood. In order to understand the rotational barrier about the C-N bond in formamide and the chalcogen analogues, a total of twelve inputs were prepared by varying the degree of rotation in a thirty degree interval rotation. The rotational barrier of C-N in formamide and in its derivatives was investigated by using density functional theory (DFT) method, employing the Beck’s three parameters exchange function combined with the Lee, Yang and Parr’s correlation function (B3LPY) using the Gaussian 03 software package. The rotational barrier of formamide and its chalcogen substituent follow the order of SFA > TFA > FA. As a result, the computational study indicates the selenoformamide had high rotational barrier than thioformamide and formamide. Keywords: Rotation barrier, Formamide, Chalcogen substutuent and optimaizationReferences
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