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QCPE
THIS INFORMATION IS OBSOLETE AND IS PROVIDED ONLY FOR ITS HISTORICAL VALUE
Main / Catalog / Section05
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358. Extended Hückel Calculation
by Eugene I. Tolpin, Department of Chemistry,
University of Louisville, Louisville, Kentucky 40208
The general program performs extended Hückel
calculations on molecules containing atoms belonging to
the first five rows of the periodic table. It is a
translated and expanded version of QCPE 256, differing
from it by allowing: 1) d orbitals to be represented
by a double zeta function; and 2) bonding to be
analzyed through bond indices and valencies according
to Armstrong, Perkins, and Stewart, and through a
Mulliken population analysis.
Extended Hückel calculation programs such as this one
use a basis set composed only of valence-shell
orbitals, in particular here, Slater-type orbitals
(STOs). The maximum number of orbitals permissible is
governed by the dimensions of various matrices. The
current form of the program allows a maximum of 150
orbitals of all types. Additional restrictions include
a maximum of 25 hydrogen atoms and 23 principle or main
atoms. The large size of these matrices in turn cause
the program to require a large amount of core (400 Kb)
for execution.
FORTRAN IV
Symbolic Cards 2747
Recommened Citation: E. I. Tolpin, QCPE 11, 358
(1978).
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