Communication: four-component density matrix renormalization group.

  title={Communication: four-component density matrix renormalization group.},
  author={Stefan Knecht and {\"O}rs Legeza and Markus Reiher},
  journal={The Journal of chemical physics},
  volume={140 4},
We present the first implementation of the relativistic quantum chemical two- and four-component density matrix renormalization group algorithm that includes a variational description of scalar-relativistic effects and spin-orbit coupling. Numerical results based on the four-component Dirac-Coulomb Hamiltonian are presented for the standard reference molecule for correlated relativistic benchmarks: thallium hydride. 

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