The atomic dipole polarizability $\ensuremath{\alpha}$ and the van der Waals (vdW) radius ${R}_{\text{vdW}}$ are two key quantities to describe vdW interactions between atoms in molecules materials. Until now, they have been determined independently separately from each other. Here, we derive quantum-mechanical relation ${R}_{\text{vdW}}=\text{const}\ifmmode\times\else\texttimes\fi{}{\ensuremath{\alpha}}^{1/7}$, which is markedly different common assumption...

Abstract The present era has seen tremendous demands for low‐cost electrochromic materials visible‐region multicolor display technology, paper‐based, flexible, and wearable electronic devices, smart windows, optoelectronic applications. Towards this goal, the authors report large‐scale, high‐yield robust polyelectrochromic devices fabricated on rigid to flexible ITO substrates comprising novel anthracene containing viologen, (1,1″‐bis(anthracen‐9‐ylmethyl)‐[4,4″‐bipyridine]‐1,1'‐diium...

Mutual Coulomb interactions between electrons lead to a plethora of interesting physical and chemical effects, especially if those involve many fluctuating over large spatial scales. Here, we identify study in detail the interaction dipolar quantum fluctuations context van der Waals complexes materials. Up now, arising from modification electron density due was considered be vanishingly small. We demonstrate that supramolecular systems for molecules embedded nanostructures, such...

It is an undisputed textbook fact that nonretarded van der Waals (vdW) interactions between isotropic dimers are attractive, regardless of the polarizability interacting systems or spatial dimensionality. The universality vdW attraction attributed to dipolar coupling fluctuating electron charge densities. Here, we demonstrate long-range interaction spatially confined becomes repulsive when accounting for full Coulomb fluctuations. Our analytic results obtained by using potential as a...

Drude oscillators provide a harmonic description of charge fluctuations and are widely studied as model system for ab initio calculations. In the dipole approximation Hamiltonian describing interaction Drudes is quadratic, so it can be diagonalized exactly, but energy diverges at short range. Here we consider quantum mechanics interacting through full Coulombic which does not have this defect. This protypical interactions between matter includes electrostatics, induction, dispersion....

Modeling intermolecular noncovalent interactions between large molecules remains a challenge for the electron structure theory community due to high cost. Fragment-based methods usually fare well in reducing cost of computations such systems. On other hand, quantum mechanical fluctuations density can be modeled by interaction atom-centered Drude oscillators. In this paper, we have developed simple yet effective method describe van der Waals based on an amalgamation oscillator with...

The dynamics of a hydrogen atom under strong, time-dependent, short-frequency magnetic field show quite interesting parametric resonance behaviour. present theoretical study reveals very rich features the interacting system, including possibility coherent emission photons and therefore new type spectroscopy using such fields. time scale calculated also suggests applications in attosecond spectroscopy.

A dynamical signature of quantum chaos is proposed in terms the nonlinear growth time-dependent (TD) distance function between two trajectories, corresponding to slightly different Hamiltonians, what defined as Ehrenfest phase space. Through comparisons this with TD correlation and Loschmidt echo case hydrogen atom strong, oscillating magnetic fields, effectiveness demonstrated.

The mechanism of ionization an H atom interacting with intense laser electric fields is altered when a strong, oscillating magnetic field applied along direction parallel to the field. In this first study, these two strongly nonperturbative situations have been combined together and corresponding time‐dependent (TD) Schrödinger equation has numerically solved without using any basis set. arising out are found be negligibly small, thereby not affecting results. There main, apparently...

The present numerical, time-dependent density-functional study of a He atom interacting with strong, oscillating magnetic fields shows that this scenario is quite different from the case laser electric field--He interaction. Signatures sluggish electron dynamics are found in study, while through mechanical analogy flow density under such conditions has been explained. These calculations take into account both exchange and correlation. Through several calculated dynamical quantities, we have...

Following the time-dependent quantum fluid density functional theory developed in our laboratory, present quantum-mechanical, dynamical study of H2 molecule under strong, oscillating magnetic fields reveals a coexistence both slow and fast dynamics, as seen earlier cases hydrogen helium atoms. Using Deb–Chattaraj equation motion we find that, contrary to situation with static fields, electron now transiently expands. Consequently, fate H–H bond such strong TD has been addressed through...

Abstract The Quantum Drude Oscillator (QDO) model is a promising candidate for accurately calculating the van der Waals (vdW) interaction. Anisotropic QDO models have recently been used to represent quantum fluctuations of molecular fragments rather than that single atoms. While this promises accurate calculation vdW energy, there significant room improvements, such as incorporating proper fragmentation method, higher‐order dispersion corrections, and so forth. present work attempts gauge...

Using a dynamical signature proposed earlier from our laboratory, quantum chaos in He atom interacting with strong, oscillating magnetic fields has been studied through comparison between the nonlinear divergence of two neighbouring Ehrenfest ‘phase-space’ (EPS) trajectories differing slightly initial conditions and Loschmidt echo. The EPS can detect independently echo agreement latter, even for low-lying states, same spirit as that classical chaos. This time-dependent extends concept to...

An accurate expression of the kinetic energy density an electronic distribution in terms a single particle reduced matrix for atomic/molecular systems is long-standing problem structure theory. Existing functionals are based on model potentials and require empirical parametrizations to fit values atoms. Moreover, correct which produces proper atomic shell still unsolved problem. In this work, we have developed exact methodology can be used systematically derive system. We also shown how...

In this work, the dynamics of electronic motion in H2+ molecule-ion under an ultrafast, strong, oscillating magnetic field have been studied and compared with those from our earlier work on H atom. Compared to atom, presence additional electron-nuclear attraction a nuclear-nuclear repulsion term molecular Hamiltonian make two sets somewhat different. particular, effective potential is not same; there now no slow dynamics; and, photoemission spectrum shows both odd even harmonics incident...

The present era has seen tremendous demands for low-cost electrochromic materials visible-region multicolor display technology, paper-based, flexible, and wearable electronic devices, smart windows, optoelectronic applications. Towards this goal, we report large-scale polyelectrochromic devices fabricated on rigid to flexible ITO substrates comprising novel anthracene containing viologen, (1,1'-bis(anthracen-9-ylmethyl)-[4,4'-bipyridine]-1,1'-diium bromide, abbreviated as AnV2+),...