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Vibrational volume

For some number of elementary sectors with given properties (heat of adsorption, vibrational volume) arbitrarily distributed on a surface, the adsorption isotherm of Langmuir,... [Pg.60]

Fig. 1. Model of non-polar liquids, left pure liquid cristal-like arrangement of molecules with T-dependent vibration volume and holes. The hole-concentration is equal the vapour concentration. right solution solutes (black) are in the holes and reduce the vapour concentration proportional to the molar concentration of the solute. Fig. 1. Model of non-polar liquids, left pure liquid cristal-like arrangement of molecules with T-dependent vibration volume and holes. The hole-concentration is equal the vapour concentration. right solution solutes (black) are in the holes and reduce the vapour concentration proportional to the molar concentration of the solute.
Where (Pfi is a universal constant having the value of 0.60, 0f% = 1 — Ofi, VfilVfii is the ratio of the hole volume to the vibrational volume (Schwingungsvolumen) of a repeat unit, and is the energy needed for the formation of a mole of holes. Since this theory was derived for the case where the end groups do not differ appreciably from the repeat units, and this is definitely not the case for the -0 Na terminated material, it was applied only to the hydroxyl terminated polymer. From a graph of IfTg vs. 1/P , shown in Fig. 2, the slope and... [Pg.66]

This is commonly the value for the mass of a resin per unit apparent bulk volume as measured by recording the minimum settled (tapped or vibrated) volume of a weighed swollen resin in water. [Pg.85]

Usually only differences of chemical potentials A//,- y - m- fjj of atoms in various crystal positions i, j are theoretically considered and because the mean vibrational volumes ti,-, vyare roughly equal, A//, y can be given, according to eq. (2.1), by the respective separation works (j> ... [Pg.20]

In this equation, Aads f corresponds to the enthalpy difference between occupied and unoccupied adsorption sites and contains Meads-s be difference of the solvation enthalpies of Meads and S. Asub is the sublimation enthalpy, which is related to the interaction enthalpy per Me bond, Hle-Me, approximated as y/i in the case of first nearest neighbors (cf. eqs. 2.2 and 2.3). The terms and Vads represent the mean vibrational volumes of an atom in a kink site position or in an adatom position, respectively [3.269]. They are related to the mean atomic vibration frequencies in the 3D Me bulk lattice and in the Meads overlayer, respectively. [Pg.57]

Determination of the excess binding energy, AT = V Mcads-s Meads-Me eq. (3.21) requires additional knowledge of the following parameters the differences of solvation energies of Meads, Me, and S, the structures of the substrate S and of the Meads overlayer reflected in c, the interaction energy within the adlayer, V Meads-Meads > and that within the 3D Me bulk phase, /Me-Me, as well the vibrational volumes and iPads Therefore, previous attempts to correlate directly AEp with physical... [Pg.57]

Vasl] Measuring of frie resonanee ultrasonic frequency excited by piezoelectrie vibrator Volume elasticity... [Pg.399]

The resultant forces of compression. Coulomb repulsion, and the recovery of dislocation of the electron pairs in the respective segment of the H-bond dominate the P-derived proton symmettization, vibration, volume compression, and phase transitional anomalies of ice under compression. [Pg.697]

Consider a gas of N non-interacting diatomic molecules moving in a tln-ee-dimensional system of volume V. Classically, the motion of a diatomic molecule has six degrees of freedom—tln-ee translational degrees corresponding to the centre of mass motion, two more for the rotational motion about the centre of mass and one additional degree for the vibrational motion about the centre of mass. The equipartition law gives (... [Pg.405]

In Equation (5.58) the outer summation is over the p points q which are used to sample the Brillouin zone, is the fractional weight associated with each point (related to the volume of Brillouin zone space surrounding q) and vi are the phonon frequencies. In addition to the internal energy due to the vibrational modes it is also possible to calculate the vibrational entropy, and hence the free energy. The Helmholtz free energy at a temperature... [Pg.313]

The molar volume is usually larger than the van der Waals volume because two additional influences must be added. The first is the amount of empty space in the bulk material due to constraints on how tightly together the chains can pack. The second is the additional space needed to accommodate the vibrational motion of the atoms at a given temperature. [Pg.313]

If we were required to pack beads in a beaker, we know from experience that by jostling the container we could achieve some compaction or decrease in free volume. In fact, we can picture the flow of a huge array of beads through a pipe by considering the beaker as a volume element in that pipe. By vibration, the beads are jostled downward that is, the holes work their way to the top. [Pg.88]

Figure 6.15 The infrared vibrational spectrum of crotonaldehyde. The parts marked (a), (b) and (c) refer to a 10 per cent (by volume) solution in CCI4, a 1 per cent solution in CCI4, and a thin liquid film, respectively. [Reproduced, with permission, from Bowles, A. J., George, W. O. and Maddams, W. F J. Chem. Soc. (B), 810, 1969]... Figure 6.15 The infrared vibrational spectrum of crotonaldehyde. The parts marked (a), (b) and (c) refer to a 10 per cent (by volume) solution in CCI4, a 1 per cent solution in CCI4, and a thin liquid film, respectively. [Reproduced, with permission, from Bowles, A. J., George, W. O. and Maddams, W. F J. Chem. Soc. (B), 810, 1969]...
Laser Raman Microprobe. A more sophisticated microscope is the Laser Raman Microprobe, sometimes referred to as MOLE (the molecular orbital laser examiner). This instmment is designed around a light microscope to yield a Raman spectmm (45) on selected areas or particles, often <1 ia volume. The data are related, at least distantly, to iafrared absorption, siace the difference between the frequency of the exciting laser and the observed Raman frequency is the frequency of one of the IR absorption peaks. Both, however, result from rotational and vibrational states. Unfortunately, strong IR absorption bands are weak Raman scatterers and vice versa hence there is no exact correspondence between the two. [Pg.335]

The dielectric constants of amino acid solutions are very high. Thek ionic dipolar structures confer special vibrational spectra (Raman, k), as well as characteristic properties (specific volumes, specific heats, electrostriction) (34). [Pg.274]

The design of smart materials and adaptive stmctures has required the development of constitutive equations that describe the temperature, stress, strain, and percentage of martensite volume transformation of a shape-memory alloy. These equations can be integrated with similar constitutive equations for composite materials to make possible the quantitative design of stmctures having embedded sensors and actuators for vibration control. The constitutive equations for one-dimensional systems as well as a three-dimensional representation have been developed (7). [Pg.465]

Molecular Nature of Steam. The molecular stmcture of steam is not as weU known as that of ice or water. During the water—steam phase change, rotation of molecules and vibration of atoms within the water molecules do not change considerably, but translation movement increases, accounting for the volume increase when water is evaporated at subcritical pressures. There are indications that even in the steam phase some H2O molecules are associated in small clusters of two or more molecules (4). Values for the dimerization enthalpy and entropy of water have been deterrnined from measurements of the pressure dependence of the thermal conductivity of water vapor at 358—386 K (85—112°C) and 13.3—133.3 kPa (100—1000 torr). These measurements yield the estimated upper limits of equiUbrium constants, for cluster formation in steam, where n is the number of molecules in a cluster. [Pg.354]


See other pages where Vibrational volume is mentioned: [Pg.117]    [Pg.112]    [Pg.20]    [Pg.388]    [Pg.323]    [Pg.584]    [Pg.602]    [Pg.117]    [Pg.112]    [Pg.20]    [Pg.388]    [Pg.323]    [Pg.584]    [Pg.602]    [Pg.830]    [Pg.1174]    [Pg.1673]    [Pg.500]    [Pg.504]    [Pg.518]    [Pg.314]    [Pg.642]    [Pg.348]    [Pg.66]    [Pg.89]    [Pg.249]    [Pg.164]    [Pg.400]    [Pg.104]    [Pg.2]    [Pg.188]    [Pg.189]    [Pg.398]    [Pg.207]    [Pg.79]    [Pg.25]    [Pg.220]    [Pg.352]   
See also in sourсe #XX -- [ Pg.19 , Pg.57 ]




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