Ensemble multicanonical

Berg B A and Neuhaus T 1992 Multicanonical ensemble—a new approach to simulate Ist-order phase transitions Phys. Rev.L 68 9-12... 

Berg, B. A. Neuhaus, T., Multicanonical ensemble a new approach to simulate first-order phase transitions, Phys. Rev. Lett. 1992, 68, 9-12... 

Hansmann, U.H.E. Okamoto, Y. Eisenmenger, F., Molecular dynamics, Langevin and hybrid Monte Carlo simulations in a multicanonical ensemble, Chem. Phys. Lett. 1996, 259, 321-330... 

Nakajima, N. Nakamura, H. Kidera, A., Multicanonical ensemble generated by molecular dynamics simulation for enhanced conformational sampling of peptides, J. Phys. Chem. B 1997,101, 817-824... 

Keywords Monte Carlo simulations polypeptides polynucleotides concerted rotations multicanonical ensemble torsional space... 

Realizations of this formalism go under the names adaptive umbrella sampling [26] and the multicanonical ensemble introduced by Berg and Neuhaus [27]. It seems right to attribute the recent revival in interest in extended sampling to the latter work. 

In the multicanonical ensemble [11,12], on the other hand, each state is weighted by a non-Boltzmann weight factor Wmn E) (which we refer to as the multicanonical weight factor), so that a uniform potential energy distribution Pmu E) is obtained ... 

The MD algorithm in the multicanonical ensemble also naturally follows from (4.17), in which the regular constant temperature MD simulation (with T = To) is performed by replacing E by Emu in (4.12) [38,42] ... 

First Order Phase Transitions and the Multicanonical Ensemble... 

One choice of generalized weights is the multicanonical ensemble [11,12] where the weight of a configuration c is defined as Wmuiticanonicai(c) oc l/g (F (c)). The multicanonical ensemble then leads to a flat histogram in energy space... 

Extended ensemble methods, such as the multicanonical ensemble, Wang-Landau sampling or parallel tempering can also be generalized to quantum systems [35,36], as we will show in the next two sections. 

For example, to perform a multicanonical ensemble simulation in the magnetization M instead of the energy J , in an Ising model (58) we consider the density of states for the magnetization g M) of the magnetization A = M = (7 and use a mixed weight... 

U. H. E. Hansmann, Y. Okamoto, and F. Eisenmengei Chem. Phys. Lett., 259, 321 (1996). Molecular Dynamics, Langevin and Hybrid Monte Carlo Simulations in Multicanonical Ensemble. 

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