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Translational freedom

Activation Parameters. Thermal processes are commonly used to break labile initiator bonds in order to form radicals. The amount of thermal energy necessary varies with the environment, but absolute temperature, T, is usually the dominant factor. The energy barrier, the minimum amount of energy that must be suppHed, is called the activation energy, E. A third important factor, known as the frequency factor, is a measure of bond motion freedom (translational, rotational, and vibrational) in the activated complex or transition state. The relationships of yi, E and T to the initiator decomposition rate (kJ) are expressed by the Arrhenius first-order rate equation (eq. 16) where R is the gas constant, and and E are known as the activation parameters. [Pg.221]

In this expression, N is the number of times a particular irreducible representation appears in the representation being reduced, h is the total number of operations in the group, is the character for a particular class of operation, jc, in the reducible representation, is the character of x in the irreducible representation, m is the number of operations in the class, and the summation is taken over all classes. The derivation of reducible representations will be covered in the next section. For now, we can illustrate use of the reduction formula by applying it to the following reducible representation, I-, for the motional degrees of freedom (translation, rotation, and vibration) in the water molecule ... [Pg.580]

In the calculation of the thermodynamic properties of the ideal gas, the approximation is made that the energies can be separated into independent contributions from the various degrees of freedom. Translational and electronic energy levels are present in the ideal monatomic gas.ww For the molecular gas, rotational and vibrational energy levels are added. For some molecules, internal rotational energy levels are also present. The equations that relate these energy levels to the mass, moments of inertia, and vibrational frequencies are summarized in Appendix 6. [Pg.31]

The presence of the above mentioned unphysical degrees of freedom translates into the fact that (i) a given component can in general be put to any value through the relevant coordinate transform and (ii) there must exist combination of the metric perturbations which remain unchanged under these coordinate transforms. The number of these quantities (called for obvious reasons gauge invariant quantities ) is precisely equal to the true number of physical degrees of freedom. [Pg.123]

The entropy of a mobile adsorption process can be determined from the model given in [4], It is based on the assumption that during the adsorption process a species in the gas phase, where it has three degrees of freedom (translation), is transferred into the adsorbed state with two translational degrees of freedom parallel to the surface and one vibration degree of freedom vertical to the surface. From statistical thermodynamics the following equation for the calculation of the adsorption entropy is derived ... [Pg.208]

Number of Atoms Total Degrees of Freedom Translational Modes Rotational Modes Vibrational Modes... [Pg.104]

These degrees of freedom also contain the so-called external degrees of freedom translations and rotations. The rotations, described by Fj, transform as the antisymmetrized square of the translations. One thus has for the external modes ... [Pg.37]

It provides a stroke of 70 pm and is designed for t3T5ical forces relevant within the front suspension. First tests have successfully been performed with loads of up to 18 kN in 2 -direction. Furthermore, it has 3 degrees of freedom (translation along z, rotation about x and y) whereas for this application only the translation is relevant. More recent versions are more compact and can be loaded even higher while providing an adapted reduced stroke. [Pg.401]

In this paper we present a classical model which describes the interaction of a visible/UV laser with a two-state system. In this model all degrees of freedom — translational, vibrational, rotational, electronic, and the laser field itself are described by classical mechanics and therefore in a dynamically consistent fashion. [Pg.639]

An argon atom has only three degrees of freedom translational motion in the X, y, and z coordinates. If the translational energy of the argon atom is 4.14 X 10 J, what is a possible translational quantum state for the atom How much energy is required to promote the atom one quantum level in each dimension The energy differences between each translational quantum level is so small at these levels (i.e. a continuum) that in statistical thermodynamics it is approximated as infinitesimal. [Pg.35]


See other pages where Translational freedom is mentioned: [Pg.103]    [Pg.514]    [Pg.230]    [Pg.82]    [Pg.60]    [Pg.230]    [Pg.190]    [Pg.351]    [Pg.228]    [Pg.141]    [Pg.63]    [Pg.74]    [Pg.153]    [Pg.4]    [Pg.47]    [Pg.196]    [Pg.70]    [Pg.183]    [Pg.471]    [Pg.64]    [Pg.125]    [Pg.616]    [Pg.173]   
See also in sourсe #XX -- [ Pg.82 ]




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