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Related papers: Ab-initio path integral techniques for molecules

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The recursion and path-integral methods are applied to analytically study the electronic structure of a neutral $C_{60}$ molecule. We employ a tight-binding Hamiltonian which considers both the $s$ and $p$ valence electrons of carbon. From…

Materials Science · Physics 2009-10-22 Yeong-Lieh Lin , Franco Nori

Path integration is a respected form of quantization that all theoretical quantum physicists should welcome. This elaboration begins with simple examples of three different versions of path integration. After an important clarification of…

General Relativity and Quantum Cosmology · Physics 2023-01-10 John R. Klauder

We derive an efficient method for the insertion of structured particles in grand canonical Monte Carlo simulations of adsorption in very confining geometries. We extend this method to path integral simulations and use it to calculate the…

Statistical Mechanics · Physics 2008-04-09 G. Garberoglio

In this work, we propose a Path Integral Monte Carlo (PIMC) approach based on discretized continuous degrees of freedom and rejection-free Gibbs sampling. The ground state properties of a chain of planar rotors with dipole-dipole…

Full $NVT$ quantum statistics of the H$_3^+$ ion is simulated at low densities using the path integral Monte Carlo approach. For the first time, the molecular total energy, partition function, free energy, entropy and heat capacity are…

Earth and Planetary Astrophysics · Physics 2011-03-22 Ilkka Kylänpää , Tapio T. Rantala

While recent work towards the development of tight-binding and ab-initio algorithms has focused on molecular dynamics, Monte Carlo methods can often lead to better results with relatively little effort. We present here a multi-step Monte…

Statistical Mechanics · Physics 2009-10-31 Parthapratim Biswas , G. T. Barkema , Normand Mousseau , W. F. van der Weg

The tensor network algorithm, a family of prevalent numerical methods for quantum many-body problems, aptly captures the entanglement properties intrinsic to quantum systems, enabling precise representation of quantum states. However, its…

Strongly Correlated Electrons · Physics 2024-06-26 He-Yu Lin , Yibin Guo , Rong-Qiang He , Z. Y. Xie , Zhong-Yi Lu

A variational Monte Carlo method is used to generate sets of orthogonal trial functions, Psi_T(J^pi,T), for given quantum numbers in various light p-shell nuclei. These Psi_T are then used as input to Green's function Monte Carlo…

Nuclear Theory · Physics 2008-11-26 Steven C. Pieper , R. B. Wiringa , J. Carlson

There is growing interest in warm dense matter (WDM) -- an exotic state on the border between condensed matter and plasmas. Due to the simultaneous importance of quantum and correlation effects WDM is complicated to treat theoretically. A…

Computational Physics · Physics 2020-10-07 Paul Hamann , Tobias Dornheim , Jan Vorberger , Zhandos A. Moldabekov , Michael Bonitz

A new parallelized simulation code is presented, which uses a Monte Carlo method to determine particle spectra in the KATRIN source. Reaction chains are generated from the decay of tritium within the source. The code includes all relevant…

Computational Physics · Physics 2025-03-14 Christian Sendlinger , Jonas Kellerer , Felix Spanier

We present extensive new \textit{ab intio} path integral Monte Carlo results for the momentum distribution function $n(\mathbf{k})$ of the uniform electron gas (UEG) in the warm dense matter (WDM) regime over a broad range of densities and…

Computational Physics · Physics 2021-05-26 Tobias Dornheim , Maximilian Böhme , Burkhard Militzer , Jan Vorberger

A path integral Monte Carlo method based on the worm algorithm has been developed to compute the chemical potential of interacting bosonic quantum fluids. By applying it to finite-sized systems of helium-4 atoms, we have confirmed that the…

Statistical Mechanics · Physics 2014-06-24 C. M. Herdman , A. Rommal , A. Del Maestro

The development and implementation of increasingly accurate methods for electronic structure calculations mean that, for many atomistic simulation problems, treating light nuclei as classical particles is now one of the most serious…

Materials Science · Physics 2016-02-12 Venkat Kapil , Joost VandeVondele , Michele Ceriotti

The quantum theory of the Friedmann cosmological model with dust and cosmological constant ($\Lambda$) is not exactly solvable analytically. We apply Path Integral Monte Carlo (PIMC) techniques to study its quantum dynamics using the…

General Relativity and Quantum Cosmology · Physics 2020-09-10 Masooma Ali , Syed Moeez Hassan , Viqar Husain

We report on a Monte Carlo method that generates one-dimensional trajectories for Bohm's formulation of quantum mechanics that doesn't involve differentiation or integration of any equations of motion. At each time, t=n\delta t…

Quantum Physics · Physics 2009-11-13 T. M. Coffey , R. E. Wyatt , W. C. Schieve

The formulation of noncommutative quantum mechanics as a quantum system represented in the space of Hilbert-Schmidt operators is used to systematically derive, using the standard time slicing procedure, the path integral action for a…

High Energy Physics - Theory · Physics 2014-02-11 Sunandan Gangopadhyay , Frederik G Scholtz

In this paper we explore new ways to study the zero temperature limit of quantum statistical mechanics using Quantum Monte Carlo simulations. We develop a Quantum Monte Carlo method in which one fixes the ground state energy as a parameter.…

Statistical Mechanics · Physics 2012-03-30 Edward Farhi , Jeffrey Goldstone , David Gosset , Harvey B. Meyer

The energy per particle of zero-temperature neutron matter is investigated, with particular emphasis on the role of the $\vec L\cdot\vec S$ interaction. An analysis of the importance of explicit spin--orbit correlations in the description…

Nuclear Theory · Physics 2009-11-10 L. Brualla , S. Fantoni , A. Sarsa , K. E Schmidt , S. A. Vitiello

The study of matter at extreme densities and temperatures has emerged as a highly active frontier at the interface of plasma physics, material science and quantum chemistry with direct relevance for planetary modeling and inertial…

We combine the recent $\eta-$ensemble path integral Monte Carlo (PIMC) approach to the free energy [T.~Dornheim \textit{et al.}, \textit{Phys.~Rev.~B} \textbf{111}, L041114 (2025)] with a recent fictitious partition function technique based…