Compressed-State Multistate Pair-Density Functional Theory.

J Chem Theory Comput

Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States.

Published: December 2020

Multiconfiguration pair-density functional theory (MC-PDFT) is a multireference method that can be used to calculate excited states. However, MC-PDFT potential energy surfaces have the wrong topology at conical intersections because the last step of MC-PDFT is not a diagonalization of a model-space Hamiltonian matrix, as done in, for example, multistate second-order perturbation theory (MS-CASPT2). We have previously proposed methods that solve this problem by diagonalizing a model-space effective Hamiltonian matrix, where the diagonal elements are MC-PDFT energies for intermediate states, and the off-diagonal elements are evaluated by wave function theory. One previous method is called variational multistate PDFT (VMS-PDFT), whose intermediate states maximize the trace of the effective Hamiltonian, namely, the sum of the MC-PDFT energies of the model-space states; the VMS-PDFT is very robust but is more computationally expensive than another method, extended multistate PDFT (XMS-PDFT), in which the transformation to intermediate states is accomplished without needing any density functional evaluations. However, although VMS-PDFT was accurate in all cases tested, XMS-PDFT was accurate in only some of them. In the present paper, we propose a new method, called compressed-state multistate PDFT (CMS-PDFT), that is as efficient as XMS-PDFT and as accurate as VMS-PDFT. The new method maximizes the trace of the classical Coulomb energy of the intermediate states such that the electron densities of the intermediate states are compressed. We show that CMS-PDFT performs robustly even where XMS-PDFT fails.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jctc.0c00908DOI Listing

Publication Analysis

Top Keywords

intermediate states
20
multistate pdft
12
compressed-state multistate
8
pair-density functional
8
functional theory
8
hamiltonian matrix
8
effective hamiltonian
8
mc-pdft energies
8
method called
8
xms-pdft accurate
8

Similar Publications

Alkylazolation of Alkenes via Photocatalytic Radical Polar Crossover.

Org Lett

January 2025

Department of Chemistry, University of Hawai'i at Ma̅noa, Honolulu, Hawaii 96822, United States.

We present a photocatalytic method for alkylamination of alkenes, enabling efficient C-C and C-N bond formation to construct aza-heterocycles valuable in drug discovery. Using a radical-polar crossover pathway, electron-deficient alkenes are reduced to electrophilic radicals, which react with electron-rich alkenes to form nucleophilic radicals. Oxidation of these intermediates yields carbocations, which are trapped by aza-heteroarenes to afford alkylaminated products.

View Article and Find Full Text PDF

Intermetallic RNiSi (R = Ca, La, and Y) Catalysts with Electron-Rich Ni Sites for Continuous Flow Selective Hydrogenation of Maleic Anhydride.

ACS Appl Mater Interfaces

January 2025

State Key Laboratory of Fine Chemicals, Laboratory of Advanced Materials and Catalytic Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.

The industrial advancement of downstream products resulting from the directed hydrogenation of maleic anhydride is hindered by the limitations related to the activity and stability of catalysts. The development of nonprecious metal intermetallic compounds, in which active sites are adjustable in the local structures and electronic properties embedded within a distinct framework, holds immense potential in enhancing catalytic efficacy and stability. Herein, we report that nickel-based silicides catalysts, RNiSi (R = Ca, La, and Y), afford high efficiency in the selective hydrogenation of maleic anhydride.

View Article and Find Full Text PDF

Insight into photocatalytic CO reduction on TiO-supported Cu nanorods: a DFT study on the reaction mechanism and selectivity.

Phys Chem Chem Phys

January 2025

State Key Laboratory of Green Chemical Engineering and Industrial Catalysis, Center for Computational Chemistry and Research Institute of Industrial Catalysis, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.

Photoreduction of CO into hydrocarbons is a potential strategy for reducing atmospheric CO and effectively utilizing carbon resources. Cu-deposited TiO photocatalysts stand out in this area due to their good photocatalytic activity and potential methanol selectivity. However, the underlying mechanism and factors controlling product selectivity remain less understood.

View Article and Find Full Text PDF

Photocatalytic Methanol Dehydrogenation with Switchable Selectivity.

J Am Chem Soc

January 2025

Department of Chemistry, University of California, Berkeley, California 94720, United States.

Switchable selectivity achieved by altering reaction conditions within the same photocatalytic system offers great advantages for sustainable chemical transformations and renewable energy conversion. In this study, we investigate an efficient photocatalytic methanol dehydrogenation with controlled selectivity by varying the concentration of nickel cocatalyst, using zinc indium sulfide nanocrystals as a semiconductor photocatalyst, which enables the production of either formaldehyde or ethylene glycol with high selectivity. Control experiments revealed that formaldehyde is initially generated and can either serve as a terminal product or intermediate in producing ethylene glycol, depending on the nickel concentration in the solution.

View Article and Find Full Text PDF

Surface State Control of Apatite Nanoparticles by pH Adjusters for Highly Biocompatible Coatings.

ACS Appl Mater Interfaces

January 2025

Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan.

Apatite nanoparticles are biocompatible nanomaterials, so their film formation on biodevices is expected to provide effective bonding with living organisms. However, the biodevice-apatite interfaces have not yet been elucidated because there is little experimental evaluation and discussion on the nanoscale interactions, as well as the apatite surface reactivities. Our group has demonstrated the biomolecular adsorption properties on a quartz crystal microbalance with dissipation (QCM-D) sensor coated with apatite nanoparticles, demonstrating the applicability of apatite nanoparticle films on devices.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!