Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Vibrating-rotator

Papousek D and Aliev M R 1982 Molecular Vibrational-Rotational Spectra (Amsterdam Elsevier)... [Pg.82]

Steinfeld J I, Francisco J S and Hase W L 1999 Chemloal KInetlos and Dynamios (Upper Saddle River, NJ Prentice-Hall) Papousek D and Aliev M R 1982 Moleoular Vibrational-Rotational Speotra (Amsterdam Elsevier)... [Pg.85]

Spectroscopic detemiination of the HE rotational distribution is another story. In both the chemical laser and infrared chemiluminescence experiments, rotational relaxation due to collisions is faster or at least comparable to the time scale of the measurements, so that accurate detemiination of the nascent rotational distribution was not feasible. However, Nesbitt [40, 41] has recently carried out direct infrared absorption experiments on the HE product under single-collision conditions, thereby obtaining a fiill vibration-rotation distribution for the nascent products. [Pg.876]

RRKM theory assumes a microcanonical ensemble of A vibrational/rotational states within the energy interval E E + dE, so that each of these states is populated statistically with an equal probability [4]. This assumption of a microcanonical distribution means that the unimolecular rate constant for A only depends on energy, and not on the maimer in which A is energized. If N(0) is the number of A molecules excited at / =... [Pg.1008]

A situation that arises from the intramolecular dynamics of A and completely distinct from apparent non-RRKM behaviour is intrinsic non-RRKM behaviour [9], By this, it is meant that A has a non-random P(t) even if the internal vibrational states of A are prepared randomly. This situation arises when transitions between individual molecular vibrational/rotational states are slower than transitions leading to products. As a result, the vibrational states do not have equal dissociation probabilities. In tenns of classical phase space dynamics, slow transitions between the states occur when the reactant phase space is metrically decomposable [13,14] on the timescale of the imimolecular reaction and there is at least one bottleneck [9] in the molecular phase space other than the one defining the transition state. An intrinsic non-RRKM molecule decays non-exponentially with a time-dependent unimolecular rate constant or exponentially with a rate constant different from that of RRKM theory. [Pg.1011]

For a RRKM calculation without any approximations, the complete vibrational/rotational Flamiltonian for the imimolecular system is used to calculate the reactant density and transition state s sum of states. No approximations are made regarding the coupling between vibration and rotation. Flowever, for many molecules the exact nature of the coupling between vibration and rotation is uncertain, particularly at high energies, and a model in which rotation and vibration are assumed separable is widely used to calculate the quantum RRKM k(E,J) [4,16]. To illustrate this model, first consider a linear polyatomic molecule which decomposes via a linear transition state. The rotational energy for tire reactant is assumed to be that for a rigid rotor, i.e. [Pg.1019]

If K is adiabatic, a molecule containing total vibrational-rotational energy E and, in a particular J, K level, has a vibrational density of states p[E - EjiJ,K). Similarly, the transition state s sum of states for the same E,J, and Kis [ -Eq-Ef(J,K)]. The RRKM rate constant for the Kadiabatic model is... [Pg.1019]

McCaffery A J 1999 Quasiresonant vibration-rotation transfer a kinematic interpretation J. Chem. Phys. Ill 7697... [Pg.1085]

H1] Qiu Y and Bai Z 1998 Vibration-rotation-tunneling dynamics of (HF)2 and (HCI)2 from fulldimensional quantum bound state calculations Advances in Moiecuiar Vibrations and Coiiision Dynamics, Voi. i-ii Moiecuiar dusters ed J Bowman and Z Bai (JAI Press) pp 183-204... [Pg.1088]

While a laser beam can be used for traditional absorption spectroscopy by measuring / and 7q, the strength of laser spectroscopy lies in more specialized experiments which often do not lend themselves to such measurements. Other techniques are connnonly used to detect the absorption of light from the laser beam. A coimnon one is to observe fluorescence excited by the laser. The total fluorescence produced is nonnally proportional to the amount of light absorbed. It can be used as a measurement of concentration to detect species present in extremely small amounts. Or a measurement of the fluorescence intensity as the laser frequency is scaimed can give an absorption spectrum. This may allow much higher resolution than is easily obtained with a traditional absorption spectrometer. In other experiments the fluorescence may be dispersed and its spectrum detennined with a traditional spectrometer. In suitable cases this could be the emission from a single electronic-vibrational-rotational level of a molecule and the experimenter can study how the spectrum varies with level. [Pg.1123]

Within physical chemistry, the long-lasting interest in IR spectroscopy lies in structural and dynamical characterization. Fligh resolution vibration-rotation spectroscopy in the gas phase reveals bond lengths, bond angles, molecular symmetry and force constants. Time-resolved IR spectroscopy characterizes reaction kinetics, vibrational lifetimes and relaxation processes. [Pg.1150]

The only tenn in this expression that we have not already seen is a, the vibration-rotation coupling constant. It accounts for the fact that as the molecule vibrates, its bond length changes which in turn changes the moment of inertia. Equation B1.2.2 can be simplified by combming the vibration-rotation constant with the rotational constant, yielding a vibrational-level-dependent rotational constant. [Pg.1153]

Liu K, Brown M G and Saykally R J 1997 Terahertz laser vibration rotation tunneling spectroscopy and dipole moment of a cage form of the water hexamer J. Phys. Chem. A 101 8995-9010... [Pg.1176]

Plenary 9. J W Nibler et al, e-mail address niblerj chem.orst.edu (CARS and SRS). High resolution studies of high lymg vibration-rotational transitions in molecules excited in electrical discharges and low density monomers and clusters in free jet expansions. Ionization detected (REMPI) SRS or IDSRS. Detect Raman... [Pg.1218]

Qotti G, Linnartz H, Meerts W L, van der Avoird A and Oithof E 1996 Stark effeot and dipoie moments of (NH3)2 in different vibration-rotation-tunneiing states J. Chem. Phys. 104 3898-906... [Pg.1262]

Cruzan J D, Viant M R, Brown M G, Luoas D D, Liu Kand Saykaiiy R J 1998 Terahertz iaser vibration-rotation-tunneiing speotrum of the water pentamer-d(IO). Constraints on the bifuroation tunneiing dynamios Chem. Phys. Lett. 292 667-76... [Pg.1262]

Keil and co-workers (Dhamiasena et al [16]) have combined the crossed-beam teclmique with a state-selective detection teclmique to measure the angular distribution of HF products, in specific vibration-rotation states, from the F + Fl2 reaction. Individual states are detected by vibrational excitation with an infrared laser and detection of the deposited energy with a bolometer [30]. [Pg.2070]

The most widely employed optical method for the study of chemical reaction dynamics has been laser-induced fluorescence. This detection scheme is schematically illustrated in the left-hand side of figure B2.3.8. A tunable laser is scanned tlnough an electronic band system of the molecule, while the fluorescence emission is detected. This maps out an action spectrum that can be used to detemiine the relative concentrations of the various vibration-rotation levels of the molecule. [Pg.2071]

Figure B2.3.14. Experimentally derived vibration-rotation populations for the NO produet from the H + NO2 reaetion [43], The fme-stnieture labels and refer to the two ways that the projeetions 2 and A of the eleetron spin and orbital angular momenta along the intemuelear axis of this open-shell ean be eoupled (D =... Figure B2.3.14. Experimentally derived vibration-rotation populations for the NO produet from the H + NO2 reaetion [43], The fme-stnieture labels and refer to the two ways that the projeetions 2 and A of the eleetron spin and orbital angular momenta along the intemuelear axis of this open-shell ean be eoupled (D =...
Recently, the state-selective detection of reaction products tluough infrared absorption on vibrational transitions has been achieved and applied to the study of HF products from the F + H2 reaction by Nesbitt and co-workers (Chapman et al [7]). The relatively low sensitivity for direct absorption has been circumvented by the use of a multi-pass absorption arrangement with a narrow-band tunable infrared laser and dual beam differential detection of the incident and transmission beams on matched detectors. A particular advantage of probing the products tluough absorption is that the absolute concentration of the product molecules in a given vibration-rotation state can be detenuined. [Pg.2085]

Each and every electronic energy state, labelled k, has a set, labelled L, of vibration/rotation energy levels k,L and wavefiinctions... [Pg.2155]

My own research efforts [4] have, for many years, involved taking into account such non-Bom-Oppen-heimer couplings, especially in cases where vibration/rotation energy transferred to electronic motions causes... [Pg.2156]

Chalasinski G, Kendall R A, Taylor H and Simons J 1988 Propensity rules for vibration-rotation induced electron detachment of diatomic anions application to NH -> NH + e J. Phys. Chem. 92 3086-91... [Pg.2192]


See other pages where Vibrating-rotator is mentioned: [Pg.170]    [Pg.419]    [Pg.419]    [Pg.200]    [Pg.438]    [Pg.446]    [Pg.875]    [Pg.1006]    [Pg.1008]    [Pg.1010]    [Pg.1019]    [Pg.1025]    [Pg.1028]    [Pg.1049]    [Pg.1075]    [Pg.1153]    [Pg.1154]    [Pg.1233]    [Pg.1255]    [Pg.2011]    [Pg.2059]    [Pg.2078]    [Pg.2084]    [Pg.2085]    [Pg.2155]    [Pg.2156]    [Pg.2439]   
See also in sourсe #XX -- [ Pg.136 ]




SEARCH



85 vibration- rotation coupling molecular beams

Absorption spectra near-infrared, vibrational-rotational

And vibration-rotation bands

Angular momentum, vibration-rotation

Angular rotationally vibrating

Approximate separation of rotations and vibrations

Approximation decoupling of rotation and vibrations

Bands, vibration-rotation

Bands, vibrational-rotational

Basic principles of electronic, vibrational and rotational spectroscopy

Body-fixed frame, vibration-rotation

Born-Oppenheimer approximation vibration-rotation Hamiltonians

Branches rotation-vibration spectra

C2H2 vibration-rotation bands

Cartesian coordinates, vibration-rotation

Cartesian coordinates, vibration-rotation Hamiltonians

Chain rules, vibration-rotation Hamiltonians

Classical mechanics vibration-rotation Hamiltonians

Classical vibrational/rotational motion

Classical vibrational/rotational motion diatomic

Classical vibrational/rotational motion polyatomic

Coriolis elements, vibration-rotation

Correlation functions rotational-vibrational

Degrees of freedom, vibrational and rotational

Diatomic molecules vibration-rotation spectra

Differentials, vibration-rotation Hamiltonians

Differentials, vibration-rotation Hamiltonians derivatives

Dimensional matrix, vibration-rotation

Directional derivatives, vibration-rotation

Directional derivatives, vibration-rotation Hamiltonians

Displacement coordinates, vibration-rotation

Distribution vibrational-rotational

Electronic, vibrational and rotational energies

Electronic-vibrational-rotational spectroscopy

Energy level diagram showing electronic, vibrational, and rotational states

Energy levels diatomic vibrational/rotational

Energy levels polyatomic vibration/rotation

Energy transfer vibration-rotation

Equilibrium Statistical Distribution of Diatomic Molecules over Vibrational-Rotational States

Excitation transfer collisions Vibrational-Rotational

Excitation vibrational and rotational

Free molecules, vibration-rotation

From rotational and vibrational

Hamiltonian rotations vibrations

Hamiltonian vibration-rotational

Hydrogen vibration-rotation

Infrared Spectroscopy. Vibration-Rotation Spectra

Infrared rotation-vibration spectra, band

Infrared rotation-vibration spectra, band types

Infrared vibration rotation tunneling

Infrared vibration rotation tunneling spectroscopy

Internal coordinates, vibration-rotation

Internal coordinates, vibration-rotation derivatives

Intramolecular vibrational-rotational energy

Intramolecular vibrational-rotational energy transfer

Inversion splitting, vibration-rotation

Kinetic energy operator vibration-rotation Hamiltonians

Lasers vibrational-rotational transitions

Lattice vibrations coupled rotational-translational

Lattice vibrations rotation interaction

Lattice vibrations rotational

Lattice vibrations tunneling rotation

Measuring vectors, vibration-rotation

Molecular motion, vibration-rotation

Molecular rotations and vibrations

Molecular spectroscopy 1 rotational and vibrational spectra

Molecular spectroscopy rotation-vibration

Molecules rotational-vibrational spectroscopy

Molecules, rotational and vibrational

Multiplication generalization, vibration-rotation

Non-Adiabatic Rotational and Vibrational Reduced Masses

Nonlinear molecules, vibration-rotation

Nuclear motions Rotation and vibration

Operator vibration-rotational

Pseudorotation, vibration-rotation

Quantum numbers rotational-vibrational spectroscopy

RRKM theory rotational-vibrational energy transfer

Raman rotational-vibrational line

Relationships between potential functions and the vibration-rotation levels

Rotating vibrating molecule

Rotation-Vibration-Electronic Energy Levels and Standard Notation

Rotation-Vibration-Electronic Spectra of Diatomic Molecules

Rotation-vibration

Rotation-vibration

Rotation-vibration band spectra

Rotation-vibration eigenstate

Rotation-vibration energy, molecular internal

Rotation-vibration hyperfine structure

Rotation-vibration interactions linear triatomic molecules

Rotation-vibration microwave spectrum

Rotation-vibration spectrum

Rotation-vibration wave equation

Rotation-vibration wave functions, electric

Rotational and Vibrational Constants

Rotational and Vibrational Constants. Internuclear Distance

Rotational and Vibrational Spectra

Rotational and vibration-rotation spectra of polyatomic molecules

Rotational and vibrational energy

Rotational and vibrational energy of molecules

Rotational and vibrational relaxation

Rotational angular momentum coupling with vibrational

Rotational constants, vibration-rotation

Rotational spectra vibrational corrections

Rotational velocity, vibrational analysis

Rotational vibrating system

Rotational vibrations

Rotational vibrations

Rotational vibrations directional motion control

Rotational vibrations excited-state fragmentation

Rotational vibrations vibration coupling

Rotational-Vibrational Spectroscopy

Rotational-vibrational

Rotational-vibrational

Rotational-vibrational bands in the mid-IR

Rotational-vibrational correlations

Rotational-vibrational coupling

Rotational-vibrational energy levels

Rotational-vibrational energy transfer

Rotational-vibrational interconversion

Rotational-vibrational lines

Rotational-vibrational quantum states

Rotational-vibrational spectra

Rotational-vibrational states

Rotational-vibrational transitions

Rotations and vibrations of the diatomic molecule

Rotor parameters, vibration-rotation

Schrodinger equation vibration-rotation Hamiltonians

Selection rules vibration-rotation transitions

Separation of the vibrational and rotational wave equations

Separation of translational, rotational and vibrational motions

Shape coordinates, vibration-rotation

Spectroscopy vibration-rotation

Spectroscopy vibration-rotational

Statistical distribution over vibrational-rotational

Statistical distribution over vibrational-rotational states

The kinetic energy operators of translation, rotation and vibrations

The statistical mechanics of vibration-rotation spectra in dense phases

The vibration-rotation spectrum

Torsion vibrations tunneling rotation

Translational, Rotational and Vibrational Relaxation

Triatomic molecule, vibration-rotation

Triatomic molecule, vibration-rotation Hamiltonians

Tunneling rotation torsional vibrational splitting

Tunneling vibration-rotation

Vector additions, vibration-rotation

Vector derivative, vibration-rotation

Vector multiplication, vibration-rotation

Vibrating rotator calculations

Vibrating rotator, energy

Vibrating-rotator eigenfunctions

Vibrating-rotator energy levels

Vibration and Rotation of a Diatomic Molecule

Vibration and rotation of molecules

Vibration rotating equipment

Vibration rotation tunnelling

Vibration rotation tunnelling spectroscopy

Vibration rotational wave function

Vibration-rotation Hamiltonians

Vibration-rotation Hamiltonians angles

Vibration-rotation Hamiltonians magnitude

Vibration-rotation Hamiltonians projections

Vibration-rotation Hamiltonians rotations

Vibration-rotation band shapes

Vibration-rotation contributions

Vibration-rotation contributions rotational constants

Vibration-rotation coupling

Vibration-rotation coupling constant

Vibration-rotation excitation

Vibration-rotation interaction

Vibration-rotation interaction constants

Vibration-rotation spectrum of hydrogen chloride

Vibration-rotation transfer

Vibration-rotation transitions

Vibration-rotation tunneling spectra

Vibration-rotation tunneling spectroscopy

Vibration-rotational spectra

Vibration-rotational-tunneling

Vibrational and Rotational Relaxation Processes

Vibrational and Rotational Spectroscopy

Vibrational and rotational product state distributions

Vibrational and rotational quantum numbers

Vibrational and rotational sublevels

Vibrational anharmonicity rotational levels

Vibrational derivatives, vibration-rotation

Vibrational energy rotational spectra

Vibrational rotational excitation

Vibrational rotational interactions, effects

Vibrational temperature from rotational

Vibrational wave function interaction with rotation

Vibrational, rotational, and

Vibrational, rotational, and for O2 from reverse ozone forming

Vibrational, rotational, and translational energy distributions

Vibrational-rotational Hamiltonian

Vibrational-rotational Raman spectra

Vibrational-rotational energy

Vibrational-rotational energy, formulas

Vibrational-rotational frequencies

Vibrational-rotational levels

Vibrational-rotational motions

Vibrational-rotational partition functions

Vibrational-rotational partition functions applications

Vibrational-rotational partition functions atom + diatom

Vibrational-rotational spectra, for frequency

Vibrational-rotational spectra, for frequency calibration

Vibrational-rotational, translational

Vibrational-rotational, translational V-R, T) energy transfer

Vibrational-to-rotational energy transfer

Vibrational/rotational interaction

Vibrationally-rotationally cold

Vibrations diatomic molecule rotational excitation

Vibrations. Force Constants. Rotational Barriers

Volume elements, vibration-rotation

Wave function, vibrational-rotational

© 2024 chempedia.info