10.1021/jp973365n.s001
América García
América
García
Jose M. Mercero
Jose M.
Mercero
Joseph E. Fowler
Joseph E.
Fowler
Jesus M. Ugalde
Jesus M.
Ugalde
Molecular and Electronic Structures of (TiXH<sub>6</sub>)<sup>0/-</sup>, X = B, Al, Ga, Compounds
American Chemical Society
1998
Bader topological analysis
TiXH 6
C 3 v
Ga
bond
kcal
minima
isomers
C 2 v
Al
1998-02-24 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Molecular_and_Electronic_Structures_of_TiXH_sub_6_sub_sup_0_-_sup_X_B_Al_Ga_Compounds/3726612
The molecular and electronic structures of the isomers of both
neutral and negative
(TiXH<sub>6</sub>)<sup>0/-</sup>, X = B,
Al,
Ga, systems have been studied. For each of the neutral systems, a
<i>C</i><sub>s</sub> isomer of signature (2, 3, 1) (where
(a,
b, c) signifies <i>a </i>is the number of terminal Ti−H bonds,
<i>b</i> is the number of hydrogen bridging bonds, and
<i>c</i>
is the number of terminal X−H bonds) was characterized as a stable
minimum. The X = Al, Ga neutral
systems also had two additional minima of signature (2, 2, 2)
(<i>C</i><sub>2</sub><i><sub>v</sub></i>) and (3, 3, 0)
(<i>C</i><sub>3</sub><i><sub>v</sub></i>). In the
anionic cases,
each system has a stable <i>C</i><i><sub>s</sub></i> structure
of signature (3, 2, 1). The X = Al, Ga systems, again showing
more
complexity, have minima on their anionic singlet potential energy
surfaces of signatures (2, 2, 2), (3, 3, 0),
and (3, 0, 3). The bonding characteristics of these various minima
have been analyzed in detail through
examination of molecular orbitals, natural bond orbitals, and Bader
topological analysis. One important
structural feature of the stable isomers is that strong hydrogen
bridging electron-deficient bonds are responsible
for holding the molecular structure together. For the neutrals,
the (2, 3, 1) and (2, 2, 2) isomers have almost
the same energy and the (3, 3, 0) isomer lies more than 30 kcal/mol
higher. However, for the anions, the
three structures with hydrogen bridging bonds are the most stable and
lie very close in energy, within 0.31
kcal/mol for X = Al and within 5.96 kcal/mol for X = Ga.
Ionization energies and electron affinities have
also been calculated and discussed.