It is common knowledge that relativistic effects are important in the chemistry of heavy
elements. As a result, polyatomic systems that contain heavy elements are involved in a …

Einstein proposed his theory of special relativity in 1905. For a long time it was believed that
this theory has no significant impact on chemistry. This view changed in the 1970s when it …

For a consistent quasi-relativistic electrons-only theory based on the first-quantized Dirac
Hamiltonian, it is desirable to eliminate the unphysical negative-energy states at energies …

A unitary transformation allows to separate (block-diagonalize) the Dirac Hamiltonian into
two parts one part: solely describes electrons, while the other gives rise to negative-energy …

Dirac‐exact relativistic methods, ie, 2‐or 1‐component methods which exactly reproduce the
one‐electron energies of the original 4‐component Dirac method, have established a …

We present an efficient algorithm for one-and two-component analytical energy gradients
with respect to nuclear displacements in the exact two-component decoupling approach to …

A quasi-relativistic implementation of NMR indirect spin–spin coupling constants is
presented. The exact two-component (X2C) Hamiltonian and its diagonal local …

Two-component quasirelativistic approaches are in principle capable of reproducing results
from fully relativistic calculations based on the four-component Dirac equation (with fixed …

A new algorithm for the two-component Normalized Elimination of the Small Component
(2cNESC) method is presented and tested in the calculation of spin-orbit (SO) splittings for a …

The analytical gradient for the two-component Normalized Elimination of the Small
Component (2c-NESC) method is presented. The 2c-NESC is a Dirac-exact method that …