arXiv subjects

Hirotaka Kitoh-Nishioka

Publications and source records attributed to Hirotaka Kitoh-Nishioka.

4 recordsLinked to original sources

arXiv2026

Photon-energy-programmable subnanometric electron birth-site control

Optical control of electron-generation sites has broadly enabled ultrafast nanoscale imaging, spectroscopy, and functional control. Existing approaches achieve nanoscale site selectivity by shaping localised optical fields around nanostructures, thereby limiting independent site selectivity within the same local-field hotspot. Here, using a single-molecule electron emitter, we show that site selectivity can instead be encoded in the electronic excitation pathway, enabling subnanometric control of electron birth sites within the same local-field hotspot. By tuning the photon energy, we selectively access molecular states of different spatial symmetry and reversibly switch the electron birth site between distinct locations in the same emitter, with the change read out directly in the far-field emission pattern. The switching depends on photon energy alone and is absent under variations in intensity or polarisation. Our results establish optical birth-site selectivity that is not dictated by the local-field distribution, opening a route to electron birth-site control through the electronic excitation pathway.

cond-mat.mes-hall↗

arXiv2016

FMO3-LCMO study of electron transfer coupling matrix element and pathway: Application to hole transfer between two triptophanes through cis- and trans-polyproline-linker systems

The linear-combination of fragment molecular orbitals with three-body correction (FMO3-LCMO) is examined for electron transfer (ET) coupling matrix elements and ET pathway analysis, with application to hole transfer between two triptophanes bridged by cis- and trans-polyproline linker conformations. A projection to the minimal-valence-plus-core FMO space was found to give sufficient accuracy with significant reduction of computational cost while avoiding the problem of linear dependence of FMOs stemming from involvement of bond detached atoms.

physics.chem-ph↗

arXiv2016

Charge-Transfer Matrix Elements by FMO-LCMO Approach: Hole Transfer in DNA with Parameter Tuned Range-Separated DFT

A scheme for computing charge-transfer matrix elements with the linear combination of fragment molecular orbitals and the 'nonempirically tuned range-separated' density functional is presented. It takes account of the self-consistent orbital relaxation induced by environmental Coulomb field and the exchange interaction in fragment pairs at low computational scaling along the system size. The accuracy was confirmed numerically on benchmark systems of imidazole and furane homo-dimer cations. Applications to hole transfers in DNA nucleobase pairs and in a $π$-stack adenine octomer highlight the effects of orbital relaxation.

physics.chem-ph↗

arXiv2016

Electron transfer pathway analysis in bacterial photosynthetic reaction center

A new computational scheme to analyze electron transfer (ET) pathways in large biomolecules is presented with applications to ETs in bacterial photosynthetic reaction center. It consists of a linear combination of fragment molecular orbitals and an electron tunneling current analysis, which enables an efficient first-principles analysis of ET pathways in large biomolecules. The scheme has been applied to the ET from menaquinone to ubiquinone via nonheme iron complex in bacterial photosynthetic reaction center. It has revealed that not only the central Fe$^{2+}$ ion but also particular histidine ligands are involved in the ET pathways in such a way to mitigate perturbations that can be caused by metal ion substitution and depletion, which elucidates the experimentally observed insensitivity of the ET rate to these perturbations.

physics.chem-ph↗