Old notices
These pages collect together notices posted on the IUCr web site in past years. They are retained for archival interest, but there is no guarantee (or likelihood) that many of the web links found in these notices will still be active.
Distinguished Lectures on Quantum Crystallography and Complementary Fields
Lecture 44: Louis Massa (Hunter College, The City University of New York, USA): "Energy formalism of an X-ray electron density of large biological molecules"
Abstract: N-representability is a crucial concept that ensures a density matrix corresponds to an N-body antisymmetric wave function. This antisymmetry is the theoretical counterpart of the experimental principle of electron indistinguishability. The variational theorem, which is key to X-ray electron density energy calculation, holds only if the density matrices involved are N-representable. For extremely large molecular systems, it becomes beneficial to express the X-ray one-body density matrix in a kernel energy method (KEM) framework. In this work, we present the explicit form of the associated N-representable two-body density matrix and discuss its application in calculating molecular energy.
The lecture is free and open to everyone; these particular lecture is expected to last ca. 45-50min + up to 15min for Q&A. Just make sure to register.
