Vibrational-rotational, translational

Currently, we evaluate the vibrational/rotational/translational entropy of the solute molecules using normal mode and classical statistical analyses. Although the use of a quasiharmonic analysis, as suggested by Schlitter24... 

It is now possible to design the experiments using molecular beams and laser techniques such that the initial vibrational, rotational, translational or electronic states of the reagent are selected or final states of products are specified. In contrast to the measurement of overall rate constants in a bulk kinetics experiment, state-to-state differential and integral cross sections can be measured for different initial states of reactants and final states of products in these sophisticated experiments. Molecular beam studies have become more common, lasers have been used to excite the reagent molecules and it has become possible to detect the product molecules by laser-induced fluorescence . These experimental studies have put forward a dramatic change in experimental study of chemical reactions at the molecular level and has culminated in what is now called state-to-state chemistry. 

Photodissociation dynamics [89,90] is one of the most active fields of current research into chemical physics. As well as the scalar attributes of product state distributions, vector correlations between the dissociating parent molecule and its photofragments are now being explored [91-93]. The majority of studies have used one or more visible or ultraviolet photons to excite the molecule to a dissociative electronically excited state, and following dissociation the vibrational, rotational, translational, and fine-structure distributions of the fragments have been measured using a variety of pump-probe laser-based detection techniques (for recent examples see references 94-100). Vibrationally mediated photodissociation, in which one photon... 

A molecule possesses different energy states rotational, vibrational, vibrational-rotational, translational, and electronic. Different types of electromagnetic radiation are capable of transforming the normal states in molecules to produce altered states. For example, UV and visible light normally produce electronic transitions from the ground state to excited states. Once the absorbing species (D) is in an excited state (D ), it can undergo a variety of processes ... 

Miklavc, A. and Smith, I.W.M. (1988) Vibrational relaxation of C2H2 and C2D2 by vibration-rotation, translation (V-R,T) energy transfer. J. Chem. Soc., Faraday Trans. 2 84,227-238. 

The vibrational excitation of COF by collision with argon atoms (1000-3000 K) has been treated bending modes were found to be more easily excited than stretching modes [2233]. The vibrational relaxation of COFj both vibrational — (rotational, translational)... 

In order to be able to compare calculated thermochemical quantities with experimental values it is necessary to take into account not only electronic energy differences, as tabulated here, but also the vibrational, rotational, translational and work (PV) energy differences5,64. The largest term is usually the vibrational energy difference, which is taken as a sum of zero-point vibrational energies for each molecular species in the chemical... 

The eomplete partition function for a system ineludes terms which refer to the different forms of energy nuelear, electronie, molecule vibration, rotation, translation and the energy of interaction between the different molecules. 

To simplify this, we know that different forms of energy, for a molecule, are independent (however, there are exceptions, e.g. the interdependence of vibrational and rotational energies of a molecrtle). Under these conditions, we can write the total energy of a molecule as the sum of different contributions by different forms of energy nucleare , electronic Sg, vibrational rotational, translational ( and interaction e/,i.e. ... 

In the present section all basic information required for understanding rotational spectroscopy is provided. We give as already assumed the Born-Oppenheimer approximation [21], which allows the separation of nuclear and electronic motion, as well as the separation of the various nuclear motions themselves (vibrational, rotational, translational). We therefore focus only on the quantum mechanics elements related to the rotational motion. 

It is therefore necessary to reformulate the J-T effect, and not only in a version for molecules, but for both - molecules and crystals. The ontological statement emanating from the extended Born-Handy formula (28.65) is essential all other considerations regarding the symmetrical properties of molecules and crystal, and of electronic states and vibration - rotation - translation modes follow as a consequence of the properties of this formula. Here is a new version of the reformulated J-T theorem ... 

The only way-out insists in the requirement, to take into account the whole electron-vibration-rotation-translational Hamiltonian. It means, that the total Hamiltonian in the crude representation, expressed in the second quantization formalism, has explicitly to contain not only the vibrational energy quanta, but also the rotational and translational ones, which originate from the kinetic secular matrix. 

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