# Michael Widom

## Professor, Physics

**Office:**Wean Hall 6305

**Phone:**412-268-7645

**Fax:**412-681-0648

**Email:**widom@cmu.edu

**Website:**http://euler.phys.cmu.edu/widom

## Education

Ph.D., University of Chicago## Research

Professor Widom's research focuses on theoretical modeling of novel materials in condensed matter and biological physics settings. Methods of statistical mechanics, quantum mechanics and computer simulation are used to investigate structure, stability and properties of these materials.

Metals in noncrystalline (nonperiodic) structures are a major focus of effort, including: Liquid metals, for example the liquid-liquid transition in supercooled silicon); Metallic glass es, which are multi-component alloys that freeze into a solid while maintaining a liquid-like structure; Quasicrystals, which are partially ordered and highly symmetric structures that are spatially quasiperiodic. These problems are addressed using first-principles total energy calculation coupled with statistical mechanics to model entire ensembles of probable structures.

Biological physics is the second major focus, including two specific projects. Virus capsids are highly symmetric protein shells that protect the viral genome. Methods of continuum mechanics and symmetry analysis are applied to identify soft modes of deformation. The RNA molecule plays many roles at the heart of gene expression, some of which such as microRNAs and riboswitches have only recently been discovered. A characteristic feature of RNA is its highly convoluted secondary structure, which are analyzed from both thermodynamic and kinetic points of view.

## Selected Publications

- Sanxi Yao, W.P. Huhn, M. Widom,
*Phase transitions of boron carbide: Pair interaction model of high carbon limit*, Solid State Sciences 47, 21 (2015) - M. Hutchinson, M. Widom,
*Enumeration of octagonal tilings*, Theoretical Computer Science 598, 40 (2015) - Khandker Quader, Michael Widom,
*Lifshitz and other transitions in alkaline-earth 122 pnictides under pressure*, Physical Review B 90, 144512 (2014) - Qin Gao, Michael Widom,
*First-principles study of bismuth films at transition-metal grain boundaries*, Physical Review B 90, 144102 (2014) - William Paul Huhn, Michael Widom, Andrew M. Cheung, Gary J. Shiflet, S. Joseph Poon, John Lewandowski,
*First-principles calculation of elastic moduli of early-late transition metal alloys*, Phys. Rev. B 89, 104103 (2014) - R. Feenstra, N. Srivastava, Qin Gao, M. Widom, Bogdan Diaconescu, Taisuke Ohta, G. Kellogg, J. Robinson, I. Vlassiouk,
*Low-energy electron reflectivity from graphene*, Phys. Rev. B 87, 41406 (2013) - Chang-You Lin, Michael Widom, Robert F. Sekerka,
*Mean-field density functional theory of a three-phase contact line*, Phys. Rev. E 85, 11120 (2012) - Ben Sauerwine, Michael Widom,
*Kinetic Monte Carlo method applied to nucleic acid hairpin folding*, Phys. Rev. E 84, 61912 (2011) - P. Ganesh, M. Widom,
*Liquid-Liquid Transition in Supercooled Silicon Determined by First-Principles Simulation*, Physical Review Letters 102, 75701 (2009) - Zheng Yang, Ivet Bahar, Michael Widom,
*Vibrational Dynamics of Icosahedrally Symmetric Biomolecular Assemblies Compared with Predictions Based on Continuum Elasticity*, Biophysical Journal 96, 4438 (2009) - M. Widom, M. Mihalkovič,
*Symmetry-broken crystal structure of elemental boron at low temperature*, Phys. Rev. B 77, 64113 (2008) - M. Widom, J. Lidmar, David Nelson,
*Soft modes near the buckling transition of icosahedral shells*, Phys. Rev. E 76, 31911 (2007) - Eric Cockayne, Mike Widom,
*Ternary Model of an Al-Cu-Co Decagonal Quasicrystal*, Physical Review Letters 81, 598 (1998) - M. Widom,
*Bethe ansatz solution of the square-triangle random tiling model*, Physical Review Letters 70, 2094 (1993)