Zobrazeno 1 - 10
of 45
pro vyhledávání: '"Stuart M. Rothstein"'
Quantum Monte Carlo assessment of density functionals for π-electron molecules: ethylene and bifuran
Publikováno v:
Molecular Physics. 117:2241-2250
We perform all-electron, pure-sampling quantum Monte Carlo (QMC) calculations on ethylene and bifuran molecules. The orbitals used for importance sampling with a single Slater determinant are gener...
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 961:29-34
Reptation quantum Monte Carlo (RQMC) is a Markov chain and Metropolis-Hastings type algorithm. In this paper RQMC-variants are implemented for the ground-state of water molecule, whereby adjustments are made to the Metropolis decision to utilize the
Autor:
Miki Nakano, Shigenori Tanaka, Heather L. Gordon, Hirofumi Watanabe, Bryan M.B. Van Schouwen, Stuart M. Rothstein
Publikováno v:
Journal of Molecular Structure: THEOCHEM. 944:12-20
We perform potential energy calculations on mutant polyglutamine peptides that were studied experimentally, and found to aggregate with varying efficiencies. Low-energy structures were generated for each peptide by simulated annealing molecular dynam
Publikováno v:
International Journal of Quantum Chemistry. 109:3229-3234
The reptation quantum Monte Carlo (RQMC) algorithm of Baroni and Moroni (Phys Rev Lett, 1999, 82, 4745) is a recent and promising development. In this approach, one generates a large number of reptiles: sets of electron configurations arising from co
Publikováno v:
The Journal of Physical Chemistry A. 112:2012-2017
Our objective is to assess the accuracy of simulated quantum Monte Carlo electron distributions of atoms and molecules. Our approach is first to model the exact electron distribution by a linear combination of gamma distribution functions, with param
Publikováno v:
Chemical Physics Letters. 445:345-349
Accurate calculation of excited state polarizabilities by diffusion Monte Carlo remains elusive. Here, the straight-forward approach based on the finite-field approximation is problematic due to the shifting of the physical nodes upon imposition of a
Autor:
Egor Ospadov, Stuart M. Rothstein
Publikováno v:
The Journal of chemical physics. 142(2)
The objective of pure-sampling quantum Monte Carlo is to calculate physical properties that are independent of the importance sampling function being employed in the calculation, save for the mismatch of its nodal hypersurface with that of the exact
Autor:
Ivana Bosa, Stuart M. Rothstein
Publikováno v:
The Journal of Chemical Physics. 121:4486-4493
We append forward walking to a diffusion Monte Carlo algorithm which maintains a fixed number of walkers. This removes the importance sampling bias of expectation values of operators which do not commute with the Hamiltonian. We demonstrate the effec
Publikováno v:
The Journal of Chemical Physics. 119:13149-13158
A number of short, Monte Carlo simulated annealing runs are performed on a highly frustrated 69-mer off-lattice model protein, consisting of a chain of 69 beads that are either hydrophobic, hydrophilic, or neutral in nature, and which demonstrably fo
Publikováno v:
The Journal of Chemical Physics. 118:1533-1540
A number of short simulated annealing runs are performed on a highly-frustrated 46-“residue” off-lattice model protein. We perform, in an iterative fashion, a principal component analysis of the 946 nonbonded interbead distances, followed by two