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Related papers: Partition theory: A very simple illustration

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We introduce a formalism to describe fractional charging of a molecule due to interactions with its environment. The interactions which induce fractional charging are contained in the Hamiltonian of the full system (molecule and…

Chemical Physics · Physics 2024-06-25 Bendik Stoa Sannes , Jacob Pedersen , Ida-Marie Hoyvik

A phenomenological model hamiltonian to describe the folding of a protein with any given sequence is proposed. The protein is thought of as a collection of pieces of helices; as a consequence its configuration space increases with the…

Soft Condensed Matter · Physics 2009-10-30 Pierpaolo Bruscolini

Density functional theory can be extended to excited states by means of a unified variational approach for passive state ensembles. This extension overcomes the restriction of the typical density functional approach to ground states, and…

Chemical Physics · Physics 2019-07-10 Tim Gould , Stefano Pittalis

We extend our density matrix embedding theory (DMET) [Phys. Rev. Lett. 109 186404 (2012)] from lattice models to the full chemical Hamiltonian. DMET allows the many-body embedding of arbitrary fragments of a quantum system, even when such…

Strongly Correlated Electrons · Physics 2013-11-15 Gerald Knizia , Garnet Kin-Lic Chan

We present a rigorous formulation of generalized Kohn-Sham density-functional theory. This provides a straightforward Kohn-Sham description of many-body systems based not only on particle-density but also on any other observable. We…

Strongly Correlated Electrons · Physics 2008-02-03 M. Valiev , G. W. Fernando

Aims. In this work we rigorously show the shortcomings of various simplifications that are used to calculate the total internal partition function. These shortcomings can lead to errors of up to 40 percent or more in the estimated partition…

Chemical Physics · Physics 2016-11-16 Andrius Popovas , Uffe G. Jørgensen

Density matrix embedding theory (Phys. Rev. Lett. 109, 186404 (2012)) and density embedding theory ((Phys. Rev. B 89, 035140 (2014)) have recently been introduced for model lattice Hamiltonians and molecular systems. In the present work,…

Chemical Physics · Physics 2016-11-25 Ireneusz W. Bulik , Weibing Chen , Gustavo E. Scuseria

We present for static density functional theory and time-dependent density functional theory calculations an all-electron method which employs high-order hierarchical finite element bases. Our mesh generation scheme, in which structured…

Materials Science · Physics 2009-08-06 Lauri Lehtovaara , Ville Havu , Martti Puska

A geometry-based density functional theory is presented for mixtures of hard spheres, hard needles and hard platelets; both the needles and the platelets are taken to be of vanishing thickness. Geometrical weight functions that are…

Soft Condensed Matter · Physics 2009-11-11 Ansgar Esztermann , Hendrik Reich , Matthias Schmidt

Density functional theory has become the workhorse of quantum physics, chemistry, and materials science. Within these fields, a broad range of applications needs to be covered. These applications range from solids to molecular systems, from…

Chemical Physics · Physics 2025-01-20 Christof Holzer , Yannick J. Franzke

The fission process is a fascinating phenomenon in which the atomic nucleus, a compact self-bound mesoscopic system, undergoes a spontaneous or induced quantum transition into two or more fragments. A predictive, accurate and precise…

Nuclear Theory · Physics 2019-10-10 J. Dobaczewski

The self consistent version of the density functional theory (DFT) is presented, which allows to calculate the ground state and dynamic properties of finite multi-electron systems such as atoms, molecules and clusters. The exact functional…

Condensed Matter · Physics 2007-05-23 M. Ya. Amusia , V. R. Shaginyan

Partition Density Functional Theory (P-DFT) is a density embedding method that partitions a molecule into fragments by minimizing the sum of fragment energies subject to a local density constraint and a global electron-number constraint. To…

Chemical Physics · Physics 2022-06-29 Kui Zhang , Adam Wasserman

A double-atom partitioning of the molecular one-electron density matrix is used to describe atoms and bonds. All calculations are performed in Hilbert space. The concept of atomic weight functions (familiar from Hirshfeld analysis of the…

A method is proposed for the characterisation of the entropy of cellular structures, based on the compactivity concept for granular packings. Hamiltonian-like volume functions are constructed both in two and in three dimensions, enabling…

Soft Condensed Matter · Physics 2009-11-11 Raphael Blumenfeld , Sam F. Edwards

In this work we give a comprehensive derivation of an exact and numerically feasible method to perform ab-initio calculations of quantum particles interacting with a quantized electromagnetic field. We present a hierachy of…

We provide an exact expression of the moment of the partition function for random energy models of finite system size, generalizing an earlier expression for a grand canonical version of the discrete random energy model presented by the…

Disordered Systems and Neural Networks · Physics 2009-11-13 Kenzo Ogure , Yoshiyuki Kabashima

Previously, the author offered a plasma-like description of quantum phenomena. This article offers a new criterion of approximation of probability density functions of quantum theories by sums of $\delta$-functions with integer coefficients…

General Physics · Physics 2025-03-17 Andrey Akhmeteli

A physically motivated equation that determines the number of electrons of a molecule is proposed based on chemical common sense. It shows that all molecules are entangled in the number of electrons and results in the fundamental assumption…

Chemical Physics · Physics 2025-02-25 Jing Kong

This paper is a first step to chase the ambitious objective of developing a mathmatical theory of living systems. The contents refer modeling large systems of interacting living entities with the aim of describing their collective behaviors…