Chemistry Reference
In-Depth Information
CHAPTER 2
Reliable Electronic Structure
Computations for Weak Noncovalent
Interactions in Clusters
Gregory S. Tschumper
Department of Chemistry and Biochemistry, University
of Mississippi, University, Mississippi
INTRODUCTION AND SCOPE
If you are reading this chapter, you are most likely already aware of the
importance of weak attractive interactions between molecules (and atoms),
such has hydrogen bonding and London dispersion forces, in chemistry and
related fields. The relatively weak interactions between uncharged molecules
(and/or atoms) are also called nonbonded interactions and sometimes collec-
tively referred to as van der Waals forces. These intermolecular forces are not
only prevalent throughout chemistry, but they often provide the governing influ-
ence in a wide variety of chemical, physical, and biological processes.
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Some
general examples include, but are certainly not limited to, solvation, condensa-
tion, crystallization, asymmetric catalysis, bulk-phase properties, directed self-
assembly of nanomaterials, chromatographic separation, micelle formation,
molecular recognition, drug transport, as well as the structure and function of
biomolecules. The initial step in HIV infection, for instance, involves the forma-
tion of a weakly bound (noncovalent) complex of the viral envelope and cellular
receptor glycoproteins, HIV-gp120 and CD4, respectively.
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The delivery
and transport of pharmaceuticals in mammals frequently occurs through
subcovalent complexation with blood-soluble proteins such as human serum
