Subject: Summary: polarizability and vdW radius for B

From: uccatvm <[email-masked]>
Date: Mon, 15 Mar 1999 13:37:26 +0000 (GMT)

Dear CCLers,

A few weeks ago, I asked for a value for the  polarizability
and the van der Waals radius for B in a covalently bonded state.
I would like to thank Wayne Steinmetz, Ajit J. Thakkar, and
Robert J. Doerksen for their helpful replies.

Wayne Steinmetz pointed me to the Allinger force field, which uses
a van der Waals radius of 2.150 for covalently bonded B in the MM3 force
field.  The epsilon value is 0.014 kcal/mole.

Ajit Thakker suggested the following papers:
Das and Thakkar, J. Physics B, 31 (1998) 2215, for the polarizability of
a free boron atom, while the polarizability of a boron atom in a
heteroatomic molecule can be found from the parameters for model 5 in the
1998 JPCA paper by RJ Doerksen and AJ Thakkar (see below).

Robert Doercksen pointed me to work from his Ph.D. thesis:
"Azaborinines: Structures, vibrational frequencies, and polarizabilities,"
J. Phys. Chem. A 102, 4679-4686 (1998), RJ Doerksen and AJ Thakkar.
In further work coming out in JPCA in 1999, their additive atom model of
polarizability for 104 planar heteroaromatic molecules containing 5 or 6
of B, C, N, and O -- fitted to ab initio MP2 polarizabilities with an
optimized basis set -- suggests that the polarizability of Boron in a
planar heteroaromatic ring is about 15 a.u.

Best regards,

Tanja
-- 
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     Tanja van Mourik                                                
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