# RI-MP2: first derivatives and global consistency

@article{Weigend1997RIMP2FD, title={RI-MP2: first derivatives and global consistency}, author={Florian Weigend and Marco H{\"a}ser}, journal={Theoretical Chemistry Accounts}, year={1997}, volume={97}, pages={331-340} }

Abstract. The evaluation of RI-MP2 first derivatives with respect to nuclear coordinates or with respect to an external electric field is described. The prefix RI indicates the use of an approximate resolution of identity in the Hilbert space of interacting charge distributions (Coulomb metric), i.e., the use of an auxiliary basis set to approximate charge distributions. The RI technique is applied to first derivatives of the MP2 correlation energy expression while the (restricted) Hartree-Fock… Expand

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