Extension of the PDDG/PM3 Semiempirical Molecular Orbital Method to Sulfur, Silicon, and Phosphorus

Ivan Tubert-Brohman, Cristiano Ruch Werneck Guimarães, and William L. Jorgensen*
Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520-8107
J. Chem. Theory Comput., 2005, 1 (5), pp 817–823
DOI: 10.1021/ct0500287
Publication Date (Web): June 25, 2005
Copyright © 2005 American Chemical Society
*

 Corresponding author email:  william.jorgensen@yale.edu.

Abstract

The PDDG/PM3 semiempirical molecular orbital method has been parametrized for molecules, ions, and complexes containing sulfur; the mean absolute error (MAE) for heats of formation, ΔHf, of 6.4 kcal/mol is 35−40% smaller than those for PM3, AM1, and MNDO/d. For completeness, parametrization was also carried out for silicon and phosphorus. For 144 silicon-containing molecules, the ΔHf MAE for PDDG/PM3, PM3, and AM1 is 11−12 kcal/mol, whereas MNDO/d yields 9.4 kcal/mol. For the limited set of 43 phosphorus-containing molecules, MNDO/d also yields the best results followed by PDDG/PM3, AM1, and PM3. The benefits of the d orbitals in MNDO/d for hypervalent compounds are apparent for silicon and phosphorus, whereas they are masked in the larger dataset for sulfur by large errors for branched compounds. Overall, for 1480 molecules, ions, and complexes containing the elements H, C, N, O, F, Si, P, S, Cl, Br, and I, the MAEs in kcal/mol for ΔHf are 6.5 (PDDG/PM3), 8.7 (PM3), 10.3 (MNDO/d), 10.8 (AM1), and 19.8 (MNDO).

View: Full Text HTML | Hi-Res PDF

Tools

History

  • Published In Issue September 13, 2005
  • Received February 11, 2005

Recommend & Share

Related Content

Other ACS content by these authors: