نتایج جستجو برای: vibrational frequencies

تعداد نتایج: 112109  

Journal: :Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy 2003
Michael W Ellzy Steven D Christesen James O Jensen Jack G Kay

We present a detailed analysis of the structure and infrared spectra of divinyl sulfoxide. The vibrational frequencies of the divinyl sulfoxide molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-311G* basis set. The molecule exists normally in a C(s) configuration. High-energy forms of divinyl s...

Journal: :Science 2007
Rachel J Cannara Matthew J Brukman Katherine Cimatu Anirudha V Sumant Steven Baldelli Robert W Carpick

Friction converts kinetic energy at sliding interfaces into lattice vibrations, but the detailed mechanisms of this process remain unresolved. Atomic force microscopy measurements reveal that changing the mass of the terminating atoms on a surface, and thus their vibrational frequencies, affects nanoscale friction substantially. We compared hydrogen- and deuterium-terminated single-crystal diam...

1998
Chris G. Van de Walle

The incorporation of H2 molecules on interstitial sites in various semiconductors is investigated using a density-functional-pseudopotential approach. The vibrational frequency of the interstitial molecules is shifted down compared to the free molecule. The results confirm a recent assignment of Raman lines to interstitial H2 in GaAs [Vetterhöffer et al., Phys. Rev. Lett. 77, 5409 (1996)], but ...

Journal: :The Journal of the Acoustical Society of America 2008
L E McNeil S Mitran

The acoustic spectrum of the mbira, a musical instrument from Africa that produces sound by the vibration of cantilevered metal rods, has been measured. It is found that the most prominent overtones present in the spectrum have frequencies that are approximately 5 and 14 times the lowest frequency. A finite-element model of the vibration of the key that takes into account the acoustic radiation...

Journal: :Journal of the American Chemical Society 2012
Sayan Bagchi Stephen D Fried Steven G Boxer

Electrostatic interactions provide a primary connection between a protein's three-dimensional structure and its function. Infrared probes are useful because vibrational frequencies of certain chemical groups, such as nitriles, are linearly sensitive to local electrostatic field and can serve as a molecular electric field meter. IR spectroscopy has been used to study electrostatic changes or flu...

ژورنال: مهندسی دریا 2014

In this study, Homotopy analysis method is employed for nonlinear vibrational analysis of marine riser subjected to variable axial loads. Mid-plane stretching effect has been considered in the model. Galerkin's decomposition technique is used to convert the Partial differential equation of the motion to nonlinear ordinary differential equation. Homotopy analysis method (HAM) is applied to find ...

2001
Lionel Goodman Karsten Krogh-Jespersen Ali G. OZkabak Richard N. Zare

A molecular beam of phenol, cooled by a supersonic expansion, is crossed at right angles by the output of a pulsed frequency-doubled dye laser, causing 1 + 1 resonance enhanced multiphoton ionization. The kinetic energy of the resulting photoelectrons is determined as a function oflaser wavelength with time-of-flight analysis, permitting the assignment of 11 vibrational frequencies for the 2BI ...

Journal: :Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy 2009
Sayyed Faramarz Tayyari Tayyebeh Bakhshi Maryam Ebrahimi Robert Erik Sammelson

The structure of beryllium acetylacetonate, Be(acac)(2), was fully optimized at the B3LYP (using the 6-31G*, 6-311G*, and 6-311++G(3df,2p) basis sets), Hartree-Fock, and the Möller-Plesset (using the 6-31G* basis set) levels. The frequency and intensity of the vibrational bands of Be(acac)(2) and its 1,3,5-(13)C; 2,4-(13)C; 3-(2)H; 3-(2)H-2,4-(18)O derivatives were obtained at the B3LYP level u...

Journal: :The Journal of experimental biology 2009
Kathleen M Lucas James F C Windmill Daniel Robert Jayne E Yack

The ears of insects exhibit a broad functional diversity with the ability to detect sounds across a wide range of frequencies and intensities. In tympanal ears, the membrane is a crucial step in the transduction of the acoustic stimulus into a neural signal. The tropical butterfly Morpho peleides has an oval-shaped membrane at the base of the forewing with an unusual dome in the middle of the s...

Journal: :Physical chemistry chemical physics : PCCP 2015
Hainam Do Nicholas A Besley

Vibrational frequencies for carbon clusters, fullerenes and nanotubes evaluated using empirical carbon-carbon potentials are presented. For linear and cyclic clusters, frequencies evaluated with the reactive empirical bond order (REBO) potential provide the closest agreement with experiment. The mean absolute deviation (MAD) between experiment and the calculated harmonic frequencies is 79 cm(-1...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید