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[reaction: see text] Cyclic phenylazomethines with methylene spacers (CPA-M) are obtained by dehydration of diamine with diketone. During the titration of CPA-M 4mer with FeCl(3), we observe two consecutive isosbestic points in the UV-vis spectra. We conclude that complexation occurs in two consecutive steps. Our analysis suggests that the stepwise metal(More)
When an all-benzenoid nanographene is linearly unzipped into oxygen-joined fragments, the oxidized benzenoid rings (aromatic sextets) selectively adopt the low-spin (DeltaS = 0) or high-spin conformation (DeltaS = 1) to yield the thermally most stable isomer. The selection of the conformation depends simply on the position of the aromatic sextets: the inner(More)
The highly enantioselective borohydride reduction of aromatic ketones or imines to the corresponding alcohols was developed in the presence of a catalytic amount of an optically active cobalt(II) complex catalyst. This enantioselective reduction is carried out using a precisely premodified borohydride with alcohols such as tetrahydrofurfuryl alcohol,(More)
The electron-attached (EA) and ionized (IP) symmetry-adapted-cluster configuration-interaction (SAC-CI) methods and their equation-of-motion coupled-cluster (EOMCC) analogs provide an elegant framework for studying open-shell systems. As shown in this study, these schemes require the presence of higher-order excitations, such as the four-particle-three-hole(More)
Mechanisms of the cycloaddition reactions of singlet difluorocarbene (CF(2)) to alkenes and disilene were studied using CASSCF, MR-MP2, CR-CC(2,3), and UB3LYP methods in combination with basis sets up to 6-311++G(3d,p). The CASSCF(4,4) energies suggest that the cycloadditions all follow the stepwise mechanism. However, energies calculated using the(More)
A new selected configuration interaction (CI) method was proposed for the potential energy surfaces of quasi-degenerate and excited states. Slater determinants are generated by sampling the first-order corrections to the target-state wave functions using the quantum Monte Carlo method in determinant space. As in the Monte Carlo (MC) CI method, the wave(More)
We report on the first application of the model space quantum Monte Carlo (MSQMC) to potential energy curves (PECs) for the excited states of C2, N2, and O2 to validate the applicability of the method. A parallel MSQMC code is implemented with the initiator approximation to enable efficient sampling. The PECs of MSQMC for various excited and ionized states(More)
Theoretical fine spectroscopy has been performed for the valence ionization spectra of furan, pyrrole, and thiophene with the symmetry-adapted-cluster configuration-interaction general-R method. The present method described that the pi(1) state interacts with the pi(3) (-2)pi*, pi(2) (-2)pi*, and pi(2) (-1)pi(3) (-1)pi* shake-up states providing the split(More)
A pebble drop divertor concept is proposed for future fusion reactor. The marked feature of this system is the use of multi-layer pebbles that consists of a central kernel and some coating layers, as a divertor surface component. By using multi-layer pebbles, pebble drop divertor have the advantages such as steady state wall pumping with low bulk tritium(More)
The reaction of O(2) with Si(111)-(7 x 7) has been studied by electron energy-loss spectroscopy at 82 K. In addition to the losses due to Si-O-Si configurations, we observed two Si-O stretch modes depending on the coverage. A 146-meV peak appears at the initial reaction stage and was ascribed to a metastable product with one oxygen atom bonding on top of Si(More)