A new partitioning scheme for molecular interacting systems within a multiconfigurational or monoconfigurational Hartree-Fock formalism

• Type: Another Publication in an International Scientific Journal
• Date: 1999

Authors

Melo, A (Author) FCUP; Ramos, MJ (Author) FCUP

Journal

Title: International Journal of Quantum Chemistry

Vol. 72

Pages: 157-176

ISSN: 0020-7608

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 6 Citations

Scopus - 5 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-001-4MM

DOI: 10.1002/(sici)1097-461x(1999)72:3<157::aid-qua1>3.3.co;2-#

Abstract (EN): A new method, based on the spatial decomposition of the reduced-density and pair-density matrices and the indistinguishable integrals formalism, is introduced to partition the molecular and stabilization energies into meaningful fragments. These are defined as entirely flexible variable-size entities, for example, atoms, group of atoms, ions, and interacting monomers. This new partitioning scheme is especially appropriated to study systems in which a directly bonded group-transfer process occurs. In these cases, the stabilization energies are partitioned into an intrafragment component, associated with the difference of intrinsic affinity to the transferred group between the involved fragments, and an interfragment component, associated with the difference of the magnitude of the interaction between the fragments in the initial and final binding complexes, This method was applied to the study of the arginine-carboxylate interactions, allowing us to have insight into what really happens in this system. Two (zwitterionic and neutral) binding complexes can be considered. The main effects accountable for the preferential stabilizations of the binding complexes are determined to be basis-set independent. The zwitterionic complex is favored by the interfragment component, while the neutral complex is favored by the larger intrinsic proton affinity of the acetate relatively to the methylguanidium. (C) 1999 John Wiley & Sons, Inc.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 20