computational strategies can be established. In this chapter, the focus is on the
energy profile representation of stoichiometric or catalytic reactions assisted by
organometallic molecular entities. The multiple factors that can influence the quality
of the calculations of the Gibbs energy profile and thus the mechanistic interpretation
of reactions with molecular organometallic complexes are presented and illustrated
by examples issued from mostly personal studies. The usual suspects to be discussed
are known: representation of molecular models of increasing size, conformational
and chemical complexity, methods and levels of calculations, successes and limitations of the density functional methods, thermodynamics corrections, spectator or
actor role of the solvent, and static vs dynamics approaches. These well-identified
points of concern are illustrated by presentation of computational studies of chemical
reactions which are in direct connection with experimental data. Even if problems
persist, this chapter aims at illustrating that one can reach a representation of the
chemical reality that can be useful to address questions of present chemical interest.
Computational chemistry is already well armed to bring meaningful energy information to numerous well-defined questions.
Keywords Chemical and theoretical models · DFT calculations · Gibbs energy
profile · Organometallic reactions · Reaction mechanism
Abbreviations
AIMD
Ab initio molecular dynamics
CCSD(T) Coupled-cluster method with single and double excitations and
perturbative triples
DFT
Density functional theory
DLPNO
Domain-based local pair natural orbital coupled cluster method with
single, double, and perturbative triple excitations
ESI-MS
Electrospray ionization mass spectrometry
HF
Hartree-Fock
IGRRHO Ideal gas/rigid rotor/harmonic oscillator
MD
Molecular dynamics
PES
Potential energy surface
1 Introduction
Computational methods based on quantum mechanical modeling are increasingly
used to provide insights into mechanistic aspects of organometallic reactions
[1, 2]. Usually calculations based on density functional theory (DFT) are employed
to locate intermediates and transition states along a reaction pathway. The underlying conceptual framework is the potential energy surface (PES) concept that
describes the total energy (electronic + nuclear) of a molecular assembly as a
2
O. Eisenstein et al.
energy profile representation of stoichiometric or catalytic reactions assisted by
organometallic molecular entities. The multiple factors that can influence the quality
of the calculations of the Gibbs energy profile and thus the mechanistic interpretation
of reactions with molecular organometallic complexes are presented and illustrated
by examples issued from mostly personal studies. The usual suspects to be discussed
are known: representation of molecular models of increasing size, conformational
and chemical complexity, methods and levels of calculations, successes and limitations of the density functional methods, thermodynamics corrections, spectator or
actor role of the solvent, and static vs dynamics approaches. These well-identified
points of concern are illustrated by presentation of computational studies of chemical
reactions which are in direct connection with experimental data. Even if problems
persist, this chapter aims at illustrating that one can reach a representation of the
chemical reality that can be useful to address questions of present chemical interest.
Computational chemistry is already well armed to bring meaningful energy information to numerous well-defined questions.
Keywords Chemical and theoretical models · DFT calculations · Gibbs energy
profile · Organometallic reactions · Reaction mechanism
Abbreviations
AIMD
Ab initio molecular dynamics
CCSD(T) Coupled-cluster method with single and double excitations and
perturbative triples
DFT
Density functional theory
DLPNO
Domain-based local pair natural orbital coupled cluster method with
single, double, and perturbative triple excitations
ESI-MS
Electrospray ionization mass spectrometry
HF
Hartree-Fock
IGRRHO Ideal gas/rigid rotor/harmonic oscillator
MD
Molecular dynamics
PES
Potential energy surface
1 Introduction
Computational methods based on quantum mechanical modeling are increasingly
used to provide insights into mechanistic aspects of organometallic reactions
[1, 2]. Usually calculations based on density functional theory (DFT) are employed
to locate intermediates and transition states along a reaction pathway. The underlying conceptual framework is the potential energy surface (PES) concept that
describes the total energy (electronic + nuclear) of a molecular assembly as a
2
O. Eisenstein et al.