Abstract
The entropy dynamics method seeks maxima for the entropy of the electron density for N atoms in a crystal cell, when the Fourier amplitudes are fixed, but their phases are unknown. By analogy with molecular dynamics, the effective potential energy is the negative entropy V = −NS. The kinetic energy is proportional to the squared velocities of the electron densities at grid points in the map. It reduces to a sum of Fourier mode rotor energies. Each rotor angle experiences a couple equal to the phase gradient of S, and local dynamical equilibrium yields a Boltzmann distribution of S Trial calculations have been made of phase averages and correlations in a centrosymmetric projection of the membrane protein bacteriorhodopsin.
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McLachlan, A.D. (1993). Crystal Phase Dynamics. In: Mohammad-Djafari, A., Demoment, G. (eds) Maximum Entropy and Bayesian Methods. Fundamental Theories of Physics, vol 53. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-2217-9_36
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DOI: https://doi.org/10.1007/978-94-017-2217-9_36
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