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Abstract In this paper, we are interested in the following question: given an arbitrary Steiner triple systemonvertices and any 3‐uniform hypertreeonvertices, is it necessary thatcontainsas a subgraph provided? We show the answer is positive for a class of hypertrees and conjecture that the answer is always positive.
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Virial relations in density embedding
Abstract The accuracy of charge‐transfer excitation energies, solvatochromic shifts, and other environmental effects calculated via various density‐embedding techniques depend critically on the approximations employed for the nonadditive noninteracting kinetic energy functional,. Approximating this functional remains an important challenge in electronic‐structure theory. To assist in the development and testing of approximations for, we derive two virial relations for fragments in molecules. These establish separate connections between the nonadditive kinetic energies of the noninteracting and interacting systems of electrons, and quantities such as the electron‐nuclear attraction forces, the partition (or embedding) energy and potential, and the Kohn‐Sham potentials of the system and its parts. We numerically verify both relations on diatomic molecules.
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- Award ID(s):
- 1900301
- PAR ID:
- 10453990
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- International Journal of Quantum Chemistry
- Volume:
- 120
- Issue:
- 21
- ISSN:
- 0020-7608
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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