A density functional theory-based chemical potential equalisation approach to molecular polarizability

The electron density changes in molecular systems in the presence of external electric fields are modeled for simplicity in terms of the induced charges and dipole moments at the individual atomic sites. A chemical potential equalisation scheme is proposed for the calculation of these quantities and hence the dipole polarizability within the framework of density functional theory based linear response theory. The resulting polarizability is expressed in terms of the contributions from individual atoms in the molecule. A few illustrative numerical calculations are shown to predict the molecular polarizabilities in good agreement with available results. The usefulness of the approach to the calculation of intermolecular interaction needed for computer simulation is highlighted

A numerical study of time-dependent schrödinger equation for multiphoton vibrational interaction of no molecule, modelled as morse oscillator, with intense far-infrared femtosecond lasers

For the NO molecule, modelled as a Morse oscillator, time-dependent (TD) nuclear Schrödinger equation has been numerically solved for the multiphoton vibrational dynamics of the molecule under a far-infrared laser of wavelength 10503 nm, and four different intensities, I = 1 × 108, 1 × 1013, 5 × 1016, and 5 × 1018 W cm-2 respectively. Starting from the vibrational ground state at zero time, various TD quantities such as the norm, dissociation probability, potential energy curve and dipole moment are examined. Rich high-harmonics generation (HHG) spectra and above-threshold dissociation (ATD) spectra, due to the multiphoton interaction of vibrational motions with the laser field, and consequent elevation to the vibrational continuum, have been obtained and analysed

Magnetic states and optical properties of single-layer carbon-doped hexagonal boron nitride

We show that carbon-doped hexagonal boron nitride (h-BN) has extraordinary properties with many possible applications. We demonstrate that the substitution-induced impurity states, associated with carbon atoms, and their interactions dictate the electronic structure and properties of C-doped h-BN. Furthermore, we show that stacking of localized impurity states in small C clusters embedded in h-BN forms a set of discrete energy levels in the wide gap of h-BN. The electronic structures of these C clusters have a plethora of applications in optics, magneto-optics, and opto-electronics

Electron in one-dimensional symmetric and asymmetric double-well potentials under intense/superintense laser fields: a numerical study based on time-dependent Schrödinger equation

The responses of an electron moving in one-dimensional symmetric and asymmetric double-well oscillator (DWO) potentials respectively are analyzed under intense and superintense laser fields by numerically solving the time-dependent Schrödinger equation and evolving the systems for 96 fs at λ = 1064 nm as well as different laser intensities. Emphasis is placed on the study of only those features which can arise from the response of a single system. A detailed investigation of multiphoton processes such as high harmonics generation and the energy spectrum (obtained by fast fourier transform of the autocorrelation function) is made. The applicability of these DWOs as model systems for the generation of attosecond pulses is examined. Furthermore, a comparison is made with atoms and molecules under similar conditions, thereby establishing a qualitative parallelism in the behavior of real atoms/molecules and these model DWO systems

Ground and excited states of one-dimensional self-interacting nonlinear oscillators through time-dependent quantum mechanics

Energy eigenvalues, probability densities, and x2r values (r = 1 to 6) of one-dimensional self-interacting nonlinear oscillators have been obtained by evolving the time-dependent Schrodinger equation in imaginary time, coupled with the minimization of energy expectation values. For excited states, the orthogonality constraint with lower states is maintained. Probability density plots for the ground and first three excited states are presented. A comparison of energy eigenvalues and probability densities plots is also made between oscillators with and without self-interaction