School of Civil and Environmental Engineering 

Ph.D. Thesis Defense Announcement 

Symmetry-adapted Density Functional Theory

By Abhiraj Sharma

Advisor: 

Dr. Phanish Suryanarayana

Committee Members:  

Dr. Phanish Suryanarayana (CEE), Dr. David Sherrill(CHEM), Dr. Arash Yavari(CEE), Dr. Ting Zhu(MECH), Dr. John E Pask(LLNL)

Date and Time:  March 2, 2022 from 12pm-2 pm

Location: https://bluejeans.com/811970587/8576?src=calendarLink

  One-dimensional nanostructures such as nanotubes, nanowires, and nanocoils have received increased attention over the past three decades due to their fascinating mechanical, electronic, optical, and thermal properties. It is common for these systems to possess some form of nontranslational symmetry, with cyclic and helical perhaps the most frequent among the symmorphic and nonsymmorphic groups, respectively. Moreover, the application of torsional deformations on 1D nanostructures and bending deformations on 2D nanostructures results in systems with these symmetries. These systems are computationally intractable for the standard density functional theory (DFT) implementations which are based on affine coordinate systems.  In this work, we present a cyclic and helical symmetry-adapted formulation and large-scale parallel implementation of real-space Kohn-Sham density functional theory. We then extend this framework to enable the study of the linear response of these systems with application to the stability of carbon nanotubes.

Complete announcement, with abstract, is attached.