Chemistry Reference
In-Depth Information
MM Multipole model
MMED Multipole model experimental density
MMPD Multipole-modeled primary density
Mp Midpoint (along an internuclear axis)
MPA Mulliken's population analysis
NBO Natural bond order
Nma Nitromalonamide
PAHB Polarization-assisted hydrogen bond
PD Primary density (usually from ab initio computations)
QTAIM Quantum theory of atoms in molecules (RFW Bader's theory)
RAHB
Resonance-assisted hydrogen bond
Rcp
Ring critical point (in RFW Bader's theory)
Rp
Reference point
SF
Source function
SSHB
Short-strong hydrogen bond
TMM
Trimethylenemethane complex
VSCC
Valence shell charge concentration (RFW Bader's theory)
1
Introduction
This chapter reviews a new chemical descriptor, first proposed by Bader and Gatti
in 1998 [
1
], and whose peculiar properties are by nature profoundly germane to the
main focus of this topic relating
electron density and chemical bonding.
The source
function enables one to view chemical bonding and other chemical paradigms from
a totally new perspective and using only information from the electron density
observable and its derivatives. It is completely independent from the tools used to
obtain the electron density, which may be derived either through experimental
techniques or with one of the many available quantum mechanical models at
different levels of complexity. While the SF has been previously introduced in
very concise sections of two general reviews [
2
,
3
] and of a topic chapter [
4
], this
represents the first dedicated, comprehensive, and critical overview on the subject.
2 The Source Function: Basic Aspects
This section briefly summarizes the main aspects of the source function (SF),
showing how it is mathematically derived and how it can be physically interpreted.
Some necessary terminology is introduced, related to the different forms (local,
integrated, or double integrated) this function may be used. Potential applications
using one of these forms are also outlined.
