A phenomenological approach to the stretching mode vibrational frequencies of defects in semiconductors is proposed. A novel quantum scale is defined in terms of the first principles pseudopotential based orbital radius rs and the principal quantum number of the element concerned. A universal linear relationship between the Sanderson electronegativity (SR ) and this quantum scale is established...

We have observed infrared absorption peaks in solid nitrogen at hydrostatic pressures as high as 7 GPa at liquid-helium temperatures. The shift in the AlSb:CSb local vibrational mode is used to precisely calibrate the pressure. For all measured pressures we also observe the n3 vibrational mode of CO2 impurities. For pressures greater than 1.9 GPa, a peak appears which we attribute to a N-N stre...

We develop a quantitative theory of the ratio R of radiative to non-radiative de-excitation based on the Dexter-Klick-Russell criterion for the occurrence of luminescence. The model invokes three essential elements: a promoting mode, an accepting mode, and a set of lattice modes which ultimately absorb the vibrational energy. The ratio R is determined by the relative population of the relaxed e...

We consider a molecular single electron transistor coupled to a vibrational mode. For some values of the bias and gate voltage transport is possible only by absorption of one ore more phonons. The system acts then as a cooler for the mechanical mode at the condition that the electron temperature is lower than the phonon temperature. The final effective temperature of the vibrational mode depend...

Classical trajectory calculations for the unimolecular dissociation of nonrotating H2O, DHO, and MuHO are reported for different distributions of energy among the three vibrational normal modes. The calculations employ a realistic energy-switching potential energy surface for the electronic ground state of the water molecule. It is found that the unimolecular decay rates vary with the vibration...

Employing extensive quantum-chemical calculations at the DFT/B3LYP and MP2 level, quartic force fields of isolated N-methylacetamide are constructed. Taking into account 24 vibrational degrees of freedom, the model is employed to perform numerically exact vibrational configuration interaction calculations of the vibrational energy relaxation of the amide I mode. It is found that the energy tran...

It has been suggested that iron in InP is compensated by a donor, related to the 2316 cm−1 local vibrational mode and previously assigned to the fully hydrogenated indium vacancy, VInH4. Using AIMPRO, an ab initio local density functional cluster code, we find that VInH4 acts as a single shallow donor. It has a triplet vibrational mode at around this value, consistent with this assignment. We a...

Information on the electronic structure of a molecule and its chemical bonds is encoded in the molecular normal vibrational modes. However, normal vibrational modes result from a coupling of local vibrational modes, which means that only the latter can provide detailed insight into bonding and other structural features. In this work, it is proven that the adiabatic internal coordinate vibration...

Femtosecond vibrational coherence spectroscopy is used to investigate the low frequency vibrational dynamics of the electron transfer heme protein, cytochrome c (cyt c). The vibrational coherence spectra of ferric cyt c have been measured as a function of excitation wavelength within the Soret band. Vibrational coherence spectra obtained with excitation between 412 and 421 nm display a strong m...

A computational approach to describe the energy relaxation of a high-frequency vibrational mode in a fluctuating heterogeneous environment is outlined. Extending previous work [H. Fujisaki, Y. Zhang, and J. E. Straub, J. Chem. Phys. 124, 144910 (2006)], second-order time-dependent perturbation theory is employed which includes the fluctuations of the parameters in the Hamiltonian within the vib...