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The shapes of three hypervalent systems of first‐row atoms FH 3 , H 4 o, and F 3 H
Author(s) -
Shillady Donald D.,
Trindle Carl
Publication year - 2009
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.560060620
Subject(s) - hypervalent molecule , basis (linear algebra) , gaussian , molecule , computational chemistry , atoms in molecules , geometry , chemistry , computation , crystallography , physics , molecular physics , mathematics , quantum mechanics , algorithm , reagent
Musher's theory of hypervalent molecules (2) accounts for the shape of numerous molecules containing second‐ and third‐row atoms of groups V, VI, and VII. In an attempt to examine the hypervalent bonding mechanism in a system free of competing d orbital effects, we consider three hypervalent systems of first‐row atoms, H 4 O, FH 3 , and HF 3 . Gaussian computations employing very small lobe‐representations of Slater‐type aos indicate that H 4 O assumes a typical hypervalent geometry, with two colinear weak OH bonds and two covalent OH bonds in a normal plane. This prediction survives an improvement in basis. Our crudest computation indicates a D 3 h geometry for FH 3 , but an improved basis leads to a T‐shaped molecule consistent with the theory of hypervalent molecules. F 3 H does not possess a stable hypervalent geometry; it is computed to be unstable relative to rare gas structure F + 3 + H ‐ . The reliability of our small basis in a system with three fluorines is questionable.