New Strategies in Modeling Electronic
Structures and Properties with
Applications to Actinides
Aleksandra Leszczyk, Paweł Tecmer and Katharina Boguslawski
Abstract This chapter discusses contemporary quantum chemical methods and
provides general insights into modern electronic structure theory with a focus on
heavy-element-containing compounds. We first give a short overview of relativistic
Hamiltonians that are frequently applied to account for relativistic effects. Then,
we scrutinize various quantum chemistry methods that approximate the N -electron
wave function. In this respect, we will review the most popular single- and multireference approaches that have been developed to model the multi-reference nature
of heavy element compounds and their ground- and excited-state electronic structures. Specifically, we introduce various flavors of post-Hartree–Fock methods and
optimization schemes like the complete active space self-consistent field method,
the configuration interaction approach, the Fock-space coupled cluster model, the
pair-coupled cluster doubles ansatz, also known as the antisymmetric product of 1
reference orbital geminal, and the density matrix renormalization group algorithm.
Furthermore, we will illustrate how concepts of quantum information theory provide us with a qualitative understanding of complex electronic structures using the
picture of interacting orbitals. While modern quantum chemistry facilitates a quantitative description of atoms and molecules as well as their properties, concepts of
quantum information theory offer new strategies for a qualitative interpretation that
can shed new light onto the chemistry of complex molecular compounds.
A. Leszczyk · P. Tecmer · K. Boguslawski (B)
Faculty of Physics, Astronomy and Informatics, Institute of Physics,
Nicolaus Copernicus University in Torun, Grudziadzka 5, 87-100 Toru´ n, Poland
e-mail: k.boguslawski@fizyka.umk.pl
A. Leszczyk
e-mail: all@fizyka.umk.pl
P. Tecmer
e-mail: ptecmer@fizyka.umk.pl
K. Boguslawski
Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarina 7,
87-100 Toru´ n, Poland
© Springer Nature Switzerland AG 2019
E. Broclawik et al. (eds.), Transition Metals in Coordination Environments,
Challenges and Advances in Computational Chemistry and Physics 29,
https://doi.org/10.1007/978-3-030-11714-6_5
121
Structures and Properties with
Applications to Actinides
Aleksandra Leszczyk, Paweł Tecmer and Katharina Boguslawski
Abstract This chapter discusses contemporary quantum chemical methods and
provides general insights into modern electronic structure theory with a focus on
heavy-element-containing compounds. We first give a short overview of relativistic
Hamiltonians that are frequently applied to account for relativistic effects. Then,
we scrutinize various quantum chemistry methods that approximate the N -electron
wave function. In this respect, we will review the most popular single- and multireference approaches that have been developed to model the multi-reference nature
of heavy element compounds and their ground- and excited-state electronic structures. Specifically, we introduce various flavors of post-Hartree–Fock methods and
optimization schemes like the complete active space self-consistent field method,
the configuration interaction approach, the Fock-space coupled cluster model, the
pair-coupled cluster doubles ansatz, also known as the antisymmetric product of 1
reference orbital geminal, and the density matrix renormalization group algorithm.
Furthermore, we will illustrate how concepts of quantum information theory provide us with a qualitative understanding of complex electronic structures using the
picture of interacting orbitals. While modern quantum chemistry facilitates a quantitative description of atoms and molecules as well as their properties, concepts of
quantum information theory offer new strategies for a qualitative interpretation that
can shed new light onto the chemistry of complex molecular compounds.
A. Leszczyk · P. Tecmer · K. Boguslawski (B)
Faculty of Physics, Astronomy and Informatics, Institute of Physics,
Nicolaus Copernicus University in Torun, Grudziadzka 5, 87-100 Toru´ n, Poland
e-mail: k.boguslawski@fizyka.umk.pl
A. Leszczyk
e-mail: all@fizyka.umk.pl
P. Tecmer
e-mail: ptecmer@fizyka.umk.pl
K. Boguslawski
Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarina 7,
87-100 Toru´ n, Poland
© Springer Nature Switzerland AG 2019
E. Broclawik et al. (eds.), Transition Metals in Coordination Environments,
Challenges and Advances in Computational Chemistry and Physics 29,
https://doi.org/10.1007/978-3-030-11714-6_5
121