In the present work, valence-bond-based compression approach for diabatization (VBCAD), previously presented in literature [J. Phys. Chem. Lett. 2020, 11, 5295–5301] case of avoided crossings, is extended to more general situation conical intersections and their vicinity. A pointwise phase-correction scheme diabatic states proposed, based on explicit use peculiarities nonorthogonality ab initio...

We show that a new glassy phase can emerge in presence of strong magnetic frustration and quantum fluctuations. It is a Valence Bond Glass. We study its properties solving the Hubbard-Heisenberg model on a Bethe lattice within the large N limit introduced by Affleck and Marston. We work out the phase diagram that contains Fermi liquid, dimer and valence bond glass phases. This new glassy phase ...

We present an atomistic potential for BiFeO(3) based on the principles of bond-valence (BV) and bond-valence vector (BVV) conservation. The validity of this model potential is tested for both canonical ensemble (NVT) and isobaric-isothermal ensemble (NPT) molecular dynamics (MD) simulations. The model reproduces the ferroelectric-to-paraelectric phase transition in both NVT and NPT MD simulati...

Estimation of structure stability is an essential issue in materials design and synthesis. Global instability index (GII) based on bond-valence method is applied as a simple indication, while density functional theory calculation is adopted for accurate evaluation of formation energy. We compare the GII and total energy of typical ABO3-type perovskite oxides and rationalize their relationship, ...

We present a direct comparison of the recently proposed valence bond entanglement entropy and the von Neumann entanglement entropy on spin-1/2 Heisenberg systems using quantum Monte Carlo and density-matrix renormalization group simulations. For one-dimensional chains we show that the valence bond entropy can be either less or greater than the von Neumann entropy; hence, it cannot provide a bou...