Bulletin of the American Physical Society
APS March Meeting 2021
Volume 66, Number 1
Monday–Friday, March 15–19, 2021; Virtual; Time Zone: Central Daylight Time, USA
Session R25: Assigning Structures to Spectra Using Density Functional Theory: Method and Applications IV
8:00 AM–11:00 AM,
Thursday, March 18, 2021
Sponsoring Unit: DCP
Chair: Benjamin Janesko, Texas Christian Univ; Giovanni Scalmani, Gaussian, Inc.
Abstract: R25.00011 : Combining multireference methods with the density matrix renormalization group*
10:48 AM–11:00 AM
Here, we present a combination of multireference configuration interaction (MR-CI) methods
with the density matrix renormalization group (DMRG). Therein, the MR-CI wavefunction is directly
approximated via the DMRG. This (1) allows for using much larger active spaces,
(2) alleviates the need for computing costly many-body density matrices,
and (3) does not require internal contraction, which decreases the variational flexibility.
Extensions of this approach to more accurate MR averaged quadratic coupled cluster,
MR linearized coupled cluster, and selected CI are straightforward.
Among others, we apply this method to the challenging chromium dimer.
*This work was supported by the US NSF via grant no. CHE-1665333.
HRL acknowledges support from the German Research Foundation (DFG) via grant LA 4442/1-1.
The American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics.
1 Physics Ellipse, College Park, MD 20740-3844
Editorial Office 1 Research Road, Ridge, NY 11961-2701 (631) 591-4000
Office of Public Affairs 529 14th St NW, Suite 1050, Washington, D.C. 20045-2001 (202) 662-8700