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.
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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 PDFACS 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 PDFPhys 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 PDFJ 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 PDFACS 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.
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