Equations of explicitly-correlated coupled-cluster methods.

  title={Equations of explicitly-correlated coupled-cluster methods.},
  author={Toru Shiozaki and M. Kamiya and So Hirata and Edward F. Valeev},
  journal={Physical chemistry chemical physics : PCCP},
  volume={10 23},
The tensor contraction expressions defining a variety of high-rank coupled-cluster energies and wave functions that include the interelectronic distances (r(12)) explicitly (CC-R12) have been derived with the aid of a newly-developed computerized symbolic algebra smith. Efficient computational sequences to perform these tensor contractions have also been suggested, defining intermediate tensors-some reusable-as a sum of binary tensor contractions. smith can elucidate the index permutation… CONTINUE READING