Accurate modelling of nonadiabatic transitions and electron-phonon interactions in extended systems is essential for understanding the charge and energy transfer in photovoltaic and photocatalytic materials. The extensive computational costs of the advanced excited state methods have stimulated the development of many approximations to study the nonadiabatic molecular dynamics (NA-MD) in solid-state and molecular materials. In this work, we present a novel ∆SCF-NA-MD methodology that aims to account for electron-hole interactions and electron-phonon back-reaction critical in modelling photoinduced nuclear dynamics. The excited states dynamics is described using the delta self-consistent field (∆SCF) technique within the density functional formalism and the trajectory surface hopping. The technique is implemented in the open-source Libra-X package freely available on the Internet (https:// github.com/Quantum-Dynamics-Hub/Libra-X). This work illustrates the general utility of the developed ∆SCF-NA-MD methodology by characterizing the excited state energies and lifetimes, reorganization energies, photoisomerization quantum yields, and by providing the mechanistic details of reactive processes in a number of organic molecules.

The Libra-X software for non-adiabatic molecular dynamics is reported. It is used to comprehensively study the charge transfer dynamics at the boron subphtalocyanine chloride (SubPc)/fullerene (C60) interface.

Structural disordeling induced by hydrostatic pressure has been observed in a wide vmiety of materials. Stannic iodide, Sni 4 , is a molecular crystal which is known to exhibit pressure-induced amorphization and metallization. Previous works including x-ray diffraction, Raman and Mossbauer measurements led to a structural model of the amorphous phase that consisted of randomly oriented chains of Sn4 tetrahedral molecules. The plimary purpose of this study is to clarify the structural disorde1ing process upon the crystal-mnorphous transformation and to search for a new crystal structure beyond the amorphous state at high pressures.We have car1ied out a high-pressure, synchrotron powder xray diffraction measurement. The present study has revealed that the initial cubic structure of Sni 4 transfonns to a new crystalline phase at 7 GPa before the amorphization begins. This second phase gradually looses its crystalline chm·acter exhibited in the diffraction pattem with increasing pressure. Diffraction pattems chm·ac-teristic of the amorphous state were observed between 20 GPa and 55 GPa. At about 60 GPa, a phase transition to the third crystalline phase takes place discontinuously. A diffraction pattern of the third phase consists of very low background and only diffraction peaks assigned to the fcc structure. This fact leads to a model of the third phase in which iodine ions are located at the ideal fcc-sites and tin ions randomly occupy, for instance, the tetral1edral sites in the fcc lattice. A very small value of its lattice constant indicates that this crystal structure results from the dissociation of Sni 4 molecules. MS18.01.02 HIGH PRESSURE X-RAY STUDY OF AlH3AND AJD3: ANOMALOUS ISOTOPE EFFECT. Stanislav P. Besedin and Andrew P. Jephcoat. Depm·tment ofEm·th Sciences, University of Oxford, Parks Road, Oxford, OXl 3PR, UKThe metal hyd1ides are of interest owing to a number of phenomena in which the quantum chm·acter of a light hydrogen atom in a metallic matlix is exhibited. We report synchrotron powder x-ray diffraction measurements at room temperature for the predominantly ionic (pm·tly covalent) hydrogen-rich metal hydlides AJH3 and AJD3 in a diamond-anvil cell to maximum pressures near 53 GPa. Aluminium hydlide has a rhombohedral unit cell (R-3c space group) with a=4.4493 A and c=ll.8037 A in hexagonal axes. It can be regm·ded as "a three-dimensional polymer" all atoms of which are linked by Al-H-Al bonds. The structure can also be desCiibed in terms of a distorted hcp matlix of hydrogen atoms. in which one third of the octahedral interstices are occupied by aluminium atoms. The pressure-volume data obtained show an unexpected difference in the compressibility between isotopes, with AJD3 more compressible at all pressures. No structural phase transition hom the rhombohedral aluminium lattice is observed in either isotope, which could be associated with the previous prediction of an insulator-to-metal transition at 46 GPa. On the basis of our data for ALH3, we expect that the pressure for which the atomic hy...

Fundamental processes of exciton scattering at organic solar-cell interfaces were studied using a one-dimensional tight-binding model and by performing a time-evolution simulation of electron–hole pair wave packets. We found the fundamental features of exciton scattering: the scattering promotes not only the dissociation of excitons and the generation of interface-bound (charge-transferred) excitons but also the transmission and reflection of excitons depending on the electron and hole interface offsets. In particular, the dissociation increases in a certain region of an interface offset, while the transmission shows resonances with higher-energy bound-exciton and interface bound-exciton states. We also studied the effects of carrier-transfer and potential modulations at the interface and the scattering of charged excitons, and we found trap dissociations where one of the carriers is trapped around the interface after the dissociation.

We have investigated the electronic structure of silver chalcogenides Ag2 X ( X = S, Se, Te) and their solid solutions using hard x-ray photoemission spectroscopy in combination with density functional theory calculations using generalized gradient approximation (GGA). By including the corrections for on-site Coulomb interactions (GGA +  U), we successfully reproduced the valence band photoemission spectra, which consist mainly of the Ag 4 d band, by calculation. The estimated values for U = 4–6 eV are slightly high for Ag 4 d electrons but are consistent with those used in previously reported structural studies. On the other hand, the magnitude of the energy gap is virtually independent of U. These results suggest the strong correlation between Ag 4 d electrons in Ag2 X compounds to have surprisingly little impact on their electron transport properties.