Ab initio studies of crystal field effects. VII. Structure of 2,3‐diketopiperazine using a 13‐molecule cluster, a calculation involving 1092 basis functions
- 1 January 1993
- journal article
- research article
- Published by Wiley in International Journal of Quantum Chemistry
- Vol. 46 (1) , 73-80
- https://doi.org/10.1002/qua.560460107
Abstract
The structure of 2,3‐diketopiperazine in a crystal phase (P21/c), modeled by a 13‐molecule cluster surrounded by point charges, was completely optimized using standard gradient procedures. The (ab initio) MIA approach was used to perform the SCF step, which using a 4‐21G basis set, involves calculations using 1092 basis functions. Results are in very good agreement with experimental (X‐ray) data, in contrast to a previous study in which a model was used consisting of only point charges. © 1993 John Wiley & Sons, Inc.Keywords
This publication has 35 references indexed in Scilit:
- Self‐consistent, nonorthogonal group function approximation. III. Approaches for modeling intermolecular interactionsJournal of Computational Chemistry, 1991
- An ab-initio study of crystal field effects: solid-state and gas-phase geometry of acetamideJournal of the American Chemical Society, 1989
- The gradient‐optimized geometry of haloperidol at the 4‐21G levelJournal of Computational Chemistry, 1989
- Ab initio calculations on large molecules: The multiplicative integral approximationJournal of Computational Chemistry, 1988
- Ab Initio Studies of Crystal Field Effects in Acetylene.Acta Chemica Scandinavica, 1988
- Ab initiocalculation of the heptamer (NH3)7as a reasonable starting point for a description of the ammonia crystalInternational Journal of Quantum Chemistry, 1983
- Structural phase stability in third-period simple metalsPhysical Review B, 1983
- L'Etude Théorique des Systèmes Périodiques. I. La Méthode LCAO-HCOInternational Journal of Quantum Chemistry, 1967
- L'Étude Théorique Des Propriétés Conductrices Des Semi‐Conducteurs OrganiquesBulletin des Sociétés Chimiques Belges, 1967
- L'Étude Théorique Des Systèmes Périodiques III. L'orthonormalisation des orbitales atomiquesBulletin des Sociétés Chimiques Belges, 1967