Mitsutaka Okumura

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We examined nearsightedness of electronic matter (NEM) of finite systems on the basis of linear response function (LRF). From the computational results of a square-well model system, the behavior of responses obviously depends on the number of electrons (N): as N increases, LRF, δρ(r)/δv(r'), decays rapidly for the distance, |r-r'|. This exemplifies that(More)
Photoluminescent compounds showing emission color changes in response to external stimuli have received considerable attention because of their wide range of applications. Here, we report the unique photoluminescence behavior of a digold(I) coordination system with trigonal-planar Au(I) centers, [Au2(dppm)3](2+) (dppm = bis(diphenylphosphino)methane). This(More)
We present the linear response function of bond-orders (LRF-BO) based on a real space integration scheme for molecular systems. As in the case of the LRF of density, the LRF-BO is defined as the response of the bond order of the molecule for the virtual perturbation. Our calculations show that the LRF-BO enables us not only to detect inductive and(More)
The standard hydrogen electrode (SHE) potential in aqueous solution was evaluated with new computational procedure that provides the Gibbs energy of a proton in aqueous solution from the experimental pK(a) value and the Gibbs energy change by deprotonation reactions of several neutral alcohol molecules. With our computational scheme, the CCSD(T)/aug-cc-pVDZ(More)
The spin-unrestricted Hartree-Fock (UHF)-based coupled cluster singles and doubles (UHF-CCSD) and Mukherjee's state-specific multireference CCSD (MkCCSD) methods are applied to four ring-opening reactions. The spin-restricted Hartree-Fock (RHF)-based CCSD (RHF-CCSD) calculations are also performed for comparison. In the case of the UHF-CCSD method, an(More)
On the basis of density-functional theory (DFT) calculations, a theoretical analysis of the exchange interactions in Ni9L2(O2CMe)8{(2-py)2CO2}4, was performed, where L is a bridging ligand, OH- (1) or N3- (2). Each magnetic interaction between the Ni spin centers is analyzed for 1 and 2 in terms of exchange integrals (J values), orbital overlap integrals (T(More)
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