Adventures in physical chemistry
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Updated: Jun 13, 2026

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
1Department of Chemistry, Stanford University, Stanford, California 94305, USA. harden@stanford.edu
Abstract:
My research has included chemical physics, electron and NMR spectroscopy, membrane biophysics, and immunology. This research was curiosity driven as well as problem and technique oriented. A theoretical equation was developed for relating nuclear hyperfine splittings to electron spin distributions in free radicals. Another equation was developed to relate NMR spectra to chemical reaction rates. Early evidence for the liquid-like properties of cell membranes was obtained through the use of paramagnetic probes (spin labels). Spin labels were used in measurements of lateral as well as transverse diffusion of phospholipids in bilayer membranes. Liquid-liquid phase separations were discovered in monolayer membranes containing phospholipids and cholesterol. In the area of immunology, it was shown that antigenic peptides bind to reconstituted class II MHC molecules in membranes and trigger specific T-helper cells.
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