Relativistic Quantum Chemistry
1. Low-cost techniques for relativistic correlation calculations
The three major aspects of electronic structure calculation are: correlation, QED, and relativity. Relativistic electronic structure calculation can use 2-or-4-component spinors as 1-particle basis functions, but the calculation is prohibitively expensive. Also, the scaling of the correlation method with the number of occupied and virtual spinors is high, which creates a computational barrier for our relativistic correlation calculations. There have been so many attempts to reduce computational cost, out of which the simplest and most effective method is to use natural spinors and Cholesky decomposition technique.
2. Theoretical study of atomic clocks.
We employ the relativistic electronic structure theory for the estimation of electric dipole polarizabilities (𝛼) of the states engaged in the clock transition of atoms and predict a precise value of the blackbody radiation shift for a clock transition, which holds paramount importance for optical clock-based experiments.
