Hierarchical optimization for neutron scattering problems

Journal Article · Wed Jun 15 00:00:00 EDT 2016 · Journal of Computational Physics

DOI:https://doi.org/10.1016/J.JCP.2016.03.017· OSTI ID:22572316

Bao, Feng ^[1]; Archibald, Rick ^[1]; Bansal, Dipanshu; Delaire, Olivier ^[2]

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1. Computer Science and Mathematics Division, Oak Ridge National Laboratory, One Bethel Valley Road, P.O. Box 2008, MS-6211, Oak Ridge, TN 37831-6211 (United States)
2. Materials Science and Technology Division, Oak Ridge National Laboratory, One Bethel Valley Road, P.O. Box 2008, MS-6118, Oak Ridge, TN 37831-6118 (United States)

We present a scalable optimization method for neutron scattering problems that determines confidence regions of simulation parameters in lattice dynamics models used to fit neutron scattering data for crystalline solids. The method uses physics-based hierarchical dimension reduction in both the computational simulation domain and the parameter space. We demonstrate for silicon that after a few iterations the method converges to parameters values (interatomic force-constants) computed with density functional theory simulations.

• OSTI ID: 22572316
• Journal Information: Journal of Computational Physics, Vol. 315; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9991
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DENSITY FUNCTIONAL METHOD
DISTRIBUTION
INTERATOMIC FORCES
NEUTRON DIFFRACTION
OPTIMIZATION
SIMULATION
SOLIDS
SPACE
STOCHASTIC PROCESSES