Computational models are becoming increasingly useful and applicable tools to complement and support experiment. Nonetheless, some barriers to further applications of theoretical models still remain. The computational cost can still grow too high for relatively large chemical systems. Simulating optical rotation in solution, for example, can involve the use of several explicit water molecules resulting in a very large system size. However, numerous approximations1-16 have been developed to reduce the computational cost with minimal loss in accuracy. We examine three local correlation methods - the projected atomic orbital (PAO) approach,14,15 the orbital specific virtual (OSV) approach,16 and the pair natural orbital (PNO) approach11-13 - applied to the calculation of chiroptical properties and excited state data using coupled cluster methods. These methods aim to reduce the virtual space for each localized occupied orbital or pair of orbitals. We test the convergence with respect to truncation thresholds, pair approximations, and the effects of truncating only doubles or both singles and doubles wavefunction parameters. (1) H. Stoll. J. Chem. Phys., 1992, 91, 8449. (2) J. Friedrich. J. Chem. Theory Comput., 2009, 5, 287. (3) H. Stoll. Mol. Phys., 2009, 109, 243. (4) S. Li, J. Shen., W. Li, and Y. Jiang. J. Chem. Phys., 2006, 125, 074109-1. (5) W. Li and P. Piechuch. J. Phys. Chem. A, 2010, 114, 6721. (6) W. Li and P. Piechuch. J. Phys. Chem. A, 2010, 114, 8644. (7) W. Li and S. Li. J. Chem. Phys., 2004, 121, 6649. (8) K. Kitaura, E. Ikeao, T. Asada, T. Nakano and M. Uebayasi. Chem. Phys. Lett., 1999, 313, 701. (9) D. Federov and K. Kitaura. J. Chem. Phys., 2005, 123, 134103-1. (10) A. Taube and R.J. Bartlett. J. Chem. Phys., 2008, 128, 164101-1. (11) F. Neese, F. Wennmohs, and A. Hansen. J. Chem. Phys., 2009, 130, 114109-1. (12) F. Neese, A. Hansen, and D. G. Liakos. J. Chem. Phys., 2009, 131, 064103-1. (13) C. Riplinger and F. Neese. J. Chem. Phys., 2013, 138, 034106-1. (14) P. Pulay. Chem. Phys. Lett., 1983, 100, 151. (15) C. Hampel and H.-J. Werner. J. Chem. Phys., 1996, 104, 6286. (16) J. Yang, G.K.-L. Chan, F. R. Manby, M. Schütz, and H.-J. Werner. J. Chem. Phys., 2012, 136, 144105-1.

Chiroptical properties and excitation data with local coupled cluster methods

249th National Meeting (2015)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.