Valence bond diatomics-in-molecules (DIM) treatment of collinear interactions of Group IIa and IIb metal atoms with hydrogen halides: Application to the CaHCl system

Alan D. Isaacson, James Muckerman

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

A recently developed formulation of the semiempirical valence bond diatomics-in-molecules (DIM) method is applied to the study of collinear MHX systems, where M is a Group IIa or IIb metal atom and X is a halogen atom. In particular, ground and excited state potential energy surfaces for reactions involving the three collinear arrangements of Ca, H, and Cl are considered. Explicit construction of the DIM Hamiltonian matrix is discussed. The resulting ground state surface for the collinear reaction Ca+ClH→CaCl+H, which exhibits a barrier of 34 kcal/mole at a rather stretched nuclear geometry, is shown to be in qualitative agreement with an ab initio surface for the analogous collinear Be+FH system. In addition, a description of the " harpooning" mechanism in the collinear reactions CaH+Cl→Ca+HCl and Cl+CaH→ClCa+H arises naturally from the calculations. Reaction pathways and reactant-to-product correlation diagrams are also discussed. A simple estimation of the sensitivity of the most prominent features of the calculated potential energy surfaces to the input diatomic fragment data demonstrates that these features cannot be attributed to errors made in those data.

Original languageEnglish
Pages (from-to)1729-1749
Number of pages21
JournalJournal of Chemical Physics
Volume73
Issue number4
Publication statusPublished - 1980

Fingerprint

Potential energy surfaces
Ground state
halides
Hydrogen
Metals
valence
Hamiltonians
Atoms
Molecules
Halogens
hydrogen
Excited states
metals
atoms
molecules
potential energy
interactions
ground state
Geometry
halogens

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this

@article{0482b510371e403091a968ea65664e1a,
title = "Valence bond diatomics-in-molecules (DIM) treatment of collinear interactions of Group IIa and IIb metal atoms with hydrogen halides: Application to the CaHCl system",
abstract = "A recently developed formulation of the semiempirical valence bond diatomics-in-molecules (DIM) method is applied to the study of collinear MHX systems, where M is a Group IIa or IIb metal atom and X is a halogen atom. In particular, ground and excited state potential energy surfaces for reactions involving the three collinear arrangements of Ca, H, and Cl are considered. Explicit construction of the DIM Hamiltonian matrix is discussed. The resulting ground state surface for the collinear reaction Ca+ClH→CaCl+H, which exhibits a barrier of 34 kcal/mole at a rather stretched nuclear geometry, is shown to be in qualitative agreement with an ab initio surface for the analogous collinear Be+FH system. In addition, a description of the {"} harpooning{"} mechanism in the collinear reactions CaH+Cl→Ca+HCl and Cl+CaH→ClCa+H arises naturally from the calculations. Reaction pathways and reactant-to-product correlation diagrams are also discussed. A simple estimation of the sensitivity of the most prominent features of the calculated potential energy surfaces to the input diatomic fragment data demonstrates that these features cannot be attributed to errors made in those data.",
author = "Isaacson, {Alan D.} and James Muckerman",
year = "1980",
language = "English",
volume = "73",
pages = "1729--1749",
journal = "Journal of Chemical Physics",
issn = "0021-9606",
publisher = "American Institute of Physics Publising LLC",
number = "4",

}

TY - JOUR

T1 - Valence bond diatomics-in-molecules (DIM) treatment of collinear interactions of Group IIa and IIb metal atoms with hydrogen halides

T2 - Application to the CaHCl system

AU - Isaacson, Alan D.

AU - Muckerman, James

PY - 1980

Y1 - 1980

N2 - A recently developed formulation of the semiempirical valence bond diatomics-in-molecules (DIM) method is applied to the study of collinear MHX systems, where M is a Group IIa or IIb metal atom and X is a halogen atom. In particular, ground and excited state potential energy surfaces for reactions involving the three collinear arrangements of Ca, H, and Cl are considered. Explicit construction of the DIM Hamiltonian matrix is discussed. The resulting ground state surface for the collinear reaction Ca+ClH→CaCl+H, which exhibits a barrier of 34 kcal/mole at a rather stretched nuclear geometry, is shown to be in qualitative agreement with an ab initio surface for the analogous collinear Be+FH system. In addition, a description of the " harpooning" mechanism in the collinear reactions CaH+Cl→Ca+HCl and Cl+CaH→ClCa+H arises naturally from the calculations. Reaction pathways and reactant-to-product correlation diagrams are also discussed. A simple estimation of the sensitivity of the most prominent features of the calculated potential energy surfaces to the input diatomic fragment data demonstrates that these features cannot be attributed to errors made in those data.

AB - A recently developed formulation of the semiempirical valence bond diatomics-in-molecules (DIM) method is applied to the study of collinear MHX systems, where M is a Group IIa or IIb metal atom and X is a halogen atom. In particular, ground and excited state potential energy surfaces for reactions involving the three collinear arrangements of Ca, H, and Cl are considered. Explicit construction of the DIM Hamiltonian matrix is discussed. The resulting ground state surface for the collinear reaction Ca+ClH→CaCl+H, which exhibits a barrier of 34 kcal/mole at a rather stretched nuclear geometry, is shown to be in qualitative agreement with an ab initio surface for the analogous collinear Be+FH system. In addition, a description of the " harpooning" mechanism in the collinear reactions CaH+Cl→Ca+HCl and Cl+CaH→ClCa+H arises naturally from the calculations. Reaction pathways and reactant-to-product correlation diagrams are also discussed. A simple estimation of the sensitivity of the most prominent features of the calculated potential energy surfaces to the input diatomic fragment data demonstrates that these features cannot be attributed to errors made in those data.

UR - http://www.scopus.com/inward/record.url?scp=20844437322&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=20844437322&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:20844437322

VL - 73

SP - 1729

EP - 1749

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 4

ER -