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Energy, rotation

MSS Molecule surface scattering [159-161] Translational and rotational energy distribution of a scattered molecular beam Quantum mechanics of scattering processes... [Pg.315]

The rotational energy of a rigid molecule is given by 7(7 + l)h /S-n- IkT, where 7 is the quantum number and 7 is the moment of inertia, but if the energy level spacing is small compared to kT, integration can replace summation in the evaluation of Q t, which becomes... [Pg.583]

Equation XVI-21 provides for the general case of a molecule having n independent ways of rotation and a moment of inertia 7 that, for an asymmetric molecule, is the (geometric) mean of the principal moments. The quantity a is the symmetry number, or the number of indistinguishable positions into which the molecule can be turned by rotations. The rotational energy and entropy are [66,67]... [Pg.583]

Figure A3.9.5. Population of rotational states versus rotational energy for NO moleeules seattered from an Ag (111) surfaee at two different ineidenee energies and at = 520 K [25] (a) E = 0.85 eV, 0. = 15° and b) E = 0.09 eV, 9. = 15°. Results at = 0.85 eV show a pronoimeed rotational rainbow. Figure A3.9.5. Population of rotational states versus rotational energy for NO moleeules seattered from an Ag (111) surfaee at two different ineidenee energies and at = 520 K [25] (a) E = 0.85 eV, 0. = 15° and b) E = 0.09 eV, 9. = 15°. Results at = 0.85 eV show a pronoimeed rotational rainbow.
Wang Z S, Darling G R and Holloway S 2000 Translation-to-rotational energy transfer in seattering of H2 moleeules from Cu(111) surfaees Surf. Sc/. 458 63... [Pg.918]

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]

The same expression applies to the transition state s rotational energy Ei(J) except that the moment of inertia /... [Pg.1019]

It is straightforward to introduce active and adiabatic treatments of K into the widely used RRKM model which represents vibration and rotation as separable and the rotations as rigid rotors [41,42]. Eor a synnnetric top, tlie rotational energy is given by... [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]

In the experimental and theoretical study of energy transfer processes which involve some of the above mechanisms, one should distingiush processes in atoms and small molecules and in large polyatomic molecules. For small molecules a frill theoretical quantum treatment is possible and even computer program packages are available [, and ], with full state to state characterization. A good example are rotational energy transfer theory and experiments on Fie + CO [M] ... [Pg.1055]

If the experunental technique has sufficient resolution, and if the molecule is fairly light, the vibronic bands discussed above will be found to have a fine structure due to transitions among rotational levels in the two states. Even when the individual rotational lines caimot be resolved, the overall shape of the vibronic band will be related to the rotational structure and its analysis may help in identifying the vibronic symmetry. The analysis of the band appearance depends on calculation of the rotational energy levels and on the selection rules and relative intensity of different rotational transitions. These both come from the fonn of the rotational wavefunctions and are treated by angnlar momentum theory. It is not possible to do more than mention a simple example here. [Pg.1139]

The simplest case is a transition in a linear molecule. In this case there is no orbital or spin angular momentum. The total angular momentum, represented by tire quantum number J, is entirely rotational angular momentum. The rotational energy levels of each state approximately fit a simple fomuila ... [Pg.1140]

Table B2.5.3. Product energy distribution for some IR laser chemical reactions. (E ) is the average relative translational energy of fragments, is the average vibrational and rotational energy of polyatomic fragments, and/ is the fraction of the total product energy appearing as translational energy [109],... Table B2.5.3. Product energy distribution for some IR laser chemical reactions. (E ) is the average relative translational energy of fragments, is the average vibrational and rotational energy of polyatomic fragments, and/ is the fraction of the total product energy appearing as translational energy [109],...
Electronic structure theory describes the motions of the electrons and produces energy surfaces and wavefiinctions. The shapes and geometries of molecules, their electronic, vibrational and rotational energy levels, as well as the interactions of these states with electromagnetic fields lie within the realm of quantum stnicture theory. [Pg.2154]

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]

Most infrared spectroscopy of complexes is carried out in tire mid-infrared, which is tire region in which tire monomers usually absorb infrared radiation. Van der Waals complexes can absorb mid-infrared radiation eitlier witli or without simultaneous excitation of intennolecular bending and stretching vibrations. The mid-infrared bands tliat contain tire most infonnation about intennolecular forces are combination bands, in which tire intennolecular vibrations are excited. Such spectra map out tire vibrational and rotational energy levels associated witli monomers in excited vibrational states and, tluis, provide infonnation on interaction potentials involving excited monomers, which may be slightly different from Arose for ground-state molecules. [Pg.2444]

The homonuclear rare gas pairs are of special interest as models for intennolecular forces, but they are quite difficult to study spectroscopically. They have no microwave or infrared spectmm. However, their vibration-rotation energy levels can be detennined from their electronic absorjDtion spectra, which he in the vacuum ultraviolet (VUV) region of the spectmm. In the most recent work, Hennan et al [24] have measured vibrational and rotational frequencies to great precision. In the case of Ar-Ar, the results have been incoriDorated into a multiproperty analysis by Aziz [25] to develop a highly accurate pair potential. [Pg.2447]

Far-infrared and mid-infrared spectroscopy usually provide the most detailed picture of the vibration-rotation energy levels in the ground electronic state. However, they are not always possible and other spectroscopic methods are also important. [Pg.2447]

Loesoh FI J and Flersehbaeh D R 1972 Ballistio meohanism for vibrational and rotational energy transfer in Ar + Csl oollisions J. Chem. Rhys. 57 2038-50... [Pg.3016]


See other pages where Energy, rotation is mentioned: [Pg.110]    [Pg.347]    [Pg.310]    [Pg.584]    [Pg.586]    [Pg.200]    [Pg.201]    [Pg.205]    [Pg.802]    [Pg.909]    [Pg.1006]    [Pg.1049]    [Pg.1243]    [Pg.1243]    [Pg.2059]    [Pg.2075]    [Pg.2075]    [Pg.2076]    [Pg.2156]    [Pg.2293]    [Pg.2448]    [Pg.2962]    [Pg.3000]    [Pg.3004]    [Pg.3007]    [Pg.3008]    [Pg.3011]    [Pg.3012]    [Pg.507]   
See also in sourсe #XX -- [ Pg.15 , Pg.323 ]




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Activation energies amino group restricted rotation

Amides—Cont rotational energy barrier

Average rotational energy

Average rotational energy transfer

Bond rotation energies

Conservation of energy equation for a rotating component

Correlation functions rotational energy

Cyclohexane rotational energy barrier

Diatomic Rotational Energy Levels and Spectroscopy

Diatomic molecule rotational energy levels

Diatomic molecule, heat capacity rotational energy

Electronic, vibrational and rotational energies

Energies for rotation

Energy Dissipation and Channel Temperature for Barrel Rotation

Energy barrier for rotation

Energy barrier rotation, butane

Energy barrier rotation, ethane

Energy barrier, to rotation

Energy bond rotational

Energy level diagram showing electronic, vibrational, and rotational states

Energy levels diatomic vibrational/rotational

Energy levels polyatomic vibration/rotation

Energy levels rotational

Energy levels rotational motion

Energy levels, diagrams rotational

Energy levels, rotational species

Energy levels, rotational torsional

Energy of activation for rotation about double bond

Energy rotation barrier, components

Energy rotational

Energy rotational

Energy rotational excitation

Energy rotational structure

Energy rotational, 7, 94-------------------thermal

Energy rotational, 78 translational

Energy transfer rotation-translation

Energy transfer vibration-rotation

Energy, electronic rotational

Ethylene rotational energy barrier

Free energy conformation rotational barriers

Influence of rotational energy

Infrared Spectroscopy rotational energy

Internal energy rotational contribution

Internal pressure rotation, energy

Internal rotational energy barrier

Intersystem crossing rotational energy transfer

Intramolecular vibrational-rotational energy

Intramolecular vibrational-rotational energy transfer

Kinetic energy of rotation

Kinetic energy operator vibration-rotation Hamiltonians

Kinetic energy, classical rotational

Kinetic energy, classical rotational translational

Laser Studies of Rotational Energy Transfer

Linear molecules rotational energy

Minimum translational/rotational energy

Molecular energies rotation

Molecular nitrogen rotational energy

Molecular rotation rotational energy levels

Molecule rotational energy

Potential energy curves rotational motion

Potential energy diagram for rotation about

Potential energy surface rotational tunneling

Propane rotational energy barrier

RRKM theory rotational-vibrational energy transfer

Rotating energy

Rotating energy

Rotation energy barrier

Rotation energy levels

Rotation energy transfer

Rotation inversion energy levels

Rotation kinetic energy

Rotation matrix energy matrices

Rotation molecular energy levels

Rotation, internal Rotational energy

Rotation, internal energy

Rotation-Vibration-Electronic Energy Levels and Standard Notation

Rotation-vibration energy, molecular internal

Rotational Constants. Potential Energy Functions

Rotational Energy Disposal

Rotational Energy Equations for the Symmetric Rotor

Rotational Energy Levels of Diatomic Molecules

Rotational activation energies

Rotational and vibrational energy

Rotational and vibrational energy of molecules

Rotational barriers ground state energy, effect

Rotational energy barrier

Rotational energy barrier alkenes

Rotational energy barrier amides

Rotational energy barrier butane

Rotational energy barrier conjugated dienes

Rotational energy barrier ethane

Rotational energy coordinates

Rotational energy diatomic

Rotational energy exchange

Rotational energy hydrogen

Rotational energy level notation

Rotational energy level states

Rotational energy levels constants)

Rotational energy levels internal

Rotational energy levels oblate

Rotational energy levels prolate

Rotational energy levels with nuclear spin/rotation interaction

Rotational energy levels, ortho

Rotational energy of molecules

Rotational energy polyatomic

Rotational energy profile

Rotational energy selection rules

Rotational energy states

Rotational energy transfer

Rotational energy transfer ionization

Rotational energy transfer resonances

Rotational energy, and

Rotational energy, diatomic molecules

Rotational energy, distribution

Rotational energy, hydrogen/silicon

Rotational energy/temperature

Rotational kinetic energy

Rotational kinetic energy operator

Rotational quantized energy levels

Rotational state, infrared energy absorption

Rotational transition energy

Rotational-Translational (RT) Energy Transfer

Rotational-vibrational energy levels

Rotational-vibrational energy transfer

Skeletal rotations energy barriers

Statistical thermodynamics rotational energy

Statistical thermodynamics rotational energy levels

Stilbene bond rotation energies

The kinetic energy operators of translation, rotation and vibrations

Vibrating rotator, energy

Vibrating-rotator energy levels

Vibrational energy rotational spectra

Vibrational, rotational, and translational energy distributions

Vibrational-rotational energy

Vibrational-rotational energy, formulas

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

Vibrational-to-rotational energy transfer

Viscous Energy Dissipation for Screw Rotation

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