In the first part of the talk, I will review basic concepts of quantum chemical density matrix renormalization group (QC-DMRG), the method of choice for calculations of strongly correlated molecular systems, which is especially suitable for treatment of one-dimensional and quasi one-dimensional problems. I will also present our recent developments on local orbital optimization matching the two-site DMRG scheme [1] and introduce MOLMPS, the massively parallel QC-DMRG implementation which is currently under development [2].
In the second part, I will introduce the recently developed method for accurate “post-DMRG” treatment of dynamic correlation based on the tailored coupled cluster (CC) theory [3] in which QC-DMRG is responsible for the proper description of non-dynamic correlation, whereas dynamic correlation is incorporated by CC [4].
[1] Ch. Krumnow and L. Veis, et al., Phys. Rev. Lett 117 (2016) 21040.
[2] L. Veis and J. Brabec, et al., in preparation.
[3] T. Kinoshita and O. Hino, et al., J. Chem. Phys. 123 (2005) 074106.
[4] L. Veis and A. Antalik, et al., J. Phys. Chem. Lett. 7 (2016) 4072.