CC2 oscillator strengths within the local framework for calculating excitation energies (LoFEx).

@article{Baudin2017CC2OS,
  title={CC2 oscillator strengths within the local framework for calculating excitation energies (LoFEx).},
  author={Pablo Baudin and Thomas Kj{\ae}rgaard and Kasper Kristensen},
  journal={The Journal of chemical physics},
  year={2017},
  volume={146 14},
  pages={
          144107
        }
}
In a recent work [P. Baudin and K. Kristensen, J. Chem. Phys. 144, 224106 (2016)], we introduced a local framework for calculating excitation energies (LoFEx), based on second-order approximated coupled cluster (CC2) linear-response theory. LoFEx is a black-box method in which a reduced excitation orbital space (XOS) is optimized to provide coupled cluster (CC) excitation energies at a reduced computational cost. In this article, we present an extension of the LoFEx algorithm to the calculation… 
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