CaltechAUTHORS
  A Caltech Library Service

Spectroscopic accuracy directly from quantum chemistry: Application to ground and excited states of beryllium dimer

Sharma, Sandeep and Yanai, Takeshi and Booth, George H. and Umrigar, C. J. and Chan, Garnet Kin-Lic (2014) Spectroscopic accuracy directly from quantum chemistry: Application to ground and excited states of beryllium dimer. Journal of Chemical Physics, 140 (10). Art. No. 104112. ISSN 0021-9606. https://resolver.caltech.edu/CaltechAUTHORS:20170113-131620432

[img] PDF - Published Version
See Usage Policy.

357Kb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20170113-131620432

Abstract

We combine explicit correlation via the canonical transcorrelation approach with the density matrix renormalization group and initiator full configuration interaction quantum Monte Carlo methods to compute a near-exact beryllium dimer curve, without the use of composite methods. In particular, our direct density matrix renormalization group calculations produce a well-depth of De = 931.2 cm^(−1) which agrees very well with recent experimentally derived estimates De = 929.7±2 cm^(−1) [J. M. Merritt, V. E. Bondybey, and M. C. Heaven, Science 324, 1548 (2009)] and De= 934.6 cm^(−1) [K. Patkowski, V. Špirko, and K. Szalewicz, Science 326, 1382 (2009)], as well the best composite theoretical estimates, De = 938±15 cm^(−1) [K. Patkowski, R. Podeszwa, and K. Szalewicz, J. Phys. Chem. A 111, 12822 (2007)] and De=935.1±10 cm^(−1) [J. Koput, Phys. Chem. Chem. Phys. 13, 20311 (2011)]. Our results suggest possible inaccuracies in the functional form of the potential used at shorter bond lengths to fit the experimental data [J. M. Merritt, V. E. Bondybey, and M. C. Heaven, Science 324, 1548 (2009)]. With the density matrix renormalization group we also compute near-exact vertical excitation energies at the equilibrium geometry. These provide non-trivial benchmarks for quantum chemical methods for excited states, and illustrate the surprisingly large error that remains for 1 ^1Σ^(−)_g state with approximate multi-reference configuration interaction and equation-of-motion coupled cluster methods. Overall, we demonstrate that explicitly correlated density matrix renormalization group and initiator full configuration interaction quantum Monte Carlo methods allow us to fully converge to the basis set and correlation limit of the non-relativistic Schrödinger equation in small molecules.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1063/1.4867383DOIArticle
http://aip.scitation.org/doi/abs/10.1063/1.4867383?journalCode=jcpPublisherArticle
ORCID:
AuthorORCID
Sharma, Sandeep0000-0002-6598-8887
Chan, Garnet Kin-Lic0000-0001-8009-6038
Additional Information:© 2014 AIP Publishing LLC. Received 24 October 2013; accepted 18 February 2014; published online 12 March 2014. This work was supported by National Science Foundation (NSF) through Grant No. NSF-CHE-1265277. T.Y. was supported in part by the Core Research for Grant-in-Aid for Scientific Research (C) (Grant No. 21550027) from Ministry of Education, Culture, Sports, Science and Technology-Japan (MEXT). C.J.U. would like to acknowledge the NSF Grant No. NSF-CHE-1112097 and the Department of Energy (DOE) Grant No. DE-SC0006650.
Funders:
Funding AgencyGrant Number
NSFCHE-1265277
Ministry of Education, Culture, Sports, Science and Technology (MEXT)21550027
NSFCHE-1112097
Department of Energy (DOE)DE-SC0006650
Issue or Number:10
Record Number:CaltechAUTHORS:20170113-131620432
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20170113-131620432
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:73490
Collection:CaltechAUTHORS
Deposited By: Donna Wrublewski
Deposited On:19 Jan 2017 23:44
Last Modified:03 Oct 2019 16:28

Repository Staff Only: item control page