# On the spin and symmetry adaptation of the density matrix renormalization group method.

@article{Zgid2008OnTS, title={On the spin and symmetry adaptation of the density matrix renormalization group method.}, author={Dominika Zgid and Marcel Nooijen}, journal={The Journal of chemical physics}, year={2008}, volume={128 1}, pages={ 014107 } }

We present a spin-adapted density matrix renormalization group (DMRG) algorithm designed to target spin and spatial symmetry states that can be difficult to obtain while using a non-spin-adapted algorithm. The algorithmic modifications that have to be introduced into the usual density matrix renormalization group scheme in order to spin adapt it are discussed, and it is demonstrated that the introduced modifications do not change the overall scaling of the method. The new approach is tested on…

## 96 Citations

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- PhysicsThe Journal of chemical physics
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### The density matrix renormalization group for ab initio quantum chemistry

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CheMPS2, the authors' free open-source spin-adapted implementation of DMRG for ab initio QC, has implemented the augmented Hessian Newton–Raphson complete active space self-consistent field method, with exact Hessian.

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