EHT Home Page
A program for Extended Hueckel Theory
Tiqing Liu and Donald G. Truhlar
Department of Chemistry and Supercomputing Institute
University of Minnesota, Minneapolis, Minnesota 55455
EHT 1.0 description:
EHT is a FORTRAN 77 program for using extended Hueckel theory to
calculate the energy of a system, analytical first derivatives of the energy
respect to the atomic Cartesian coordinates, and the Mulliken atomic
The calculations include overlap in the secular equation, and the
matrix is evaluated by the Wolfsberg-Helmholz approximation. No core
term is included. The basis functions are Slater-type orbitals (STOs). In
program, d subshells are described by a contracted double zeta STO basis,
and p subshells are each described by a single zeta STO basis. Overlap
are evaluated by the method of Jones and Weatherford. The program contains
parameters for the following elements: H-Cs (noble gas elements are
La-Sm. Parameters are taken from QCPE Program 571 except for Ag; the Ag
are from Anderson, McDevitt, and Urbach (see reference in Section 2).
EHT 1.0 Manual:
- text format
Licensing and downloading:
EHT - version 1.0 is licensed under the Apache License, Version 2.0.
The manual of EHT - version 1.0 is licensed under CC-BY-4.0.
Publications of results obtained with the EHT - version 1.0 software should cite the program and/or the article describing the program.
No guarantee is made that this software is bug-free or suitable for specific applications, and no liability is accepted for any limitations in the mathematical methods and algorithms used within. No consulting or maintenance services are guaranteed or implied.
The use of the EHT - version 1.0 implies acceptance of the terms of the licenses. The software may be downloaded here.