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Internal freedom

From X-ray measurements in the liquid crystalline phase it is impossible to determine the conformation of the molecules in the condensed state. Computer simulations give us information about the molecules internal freedom in vacuum, but the conformations of the molecules in the condensed state can be different because of intermolecular repulsion or attraction. But it may be assumed that the molecular conformations in the solid state are among the most stable conformations of the molecules in the condensed matter and therefore also among the most probable conformations in the liquid crystalline state. Thus, as more crystallo-graphically independent molecules in the unit cell exist, the more we can learn about the internal molecular freedom of the molecules in the condensed state. [Pg.192]

The consequences of this relative internal freedom of thermal motion for the conformations of a chain containing a large number of bonds are profound. It was realized by several of Staudinger s contemporaries (14) although not by him, that a statistical distribution of possible bond configurations necessarily results in a statistical distribution of overall chain conformations. The average represents a loose coil rather than an extended structure with dimensions increasing as and p at most a small... [Pg.49]

The isolated rest state of a given particle at infinity in vacuum (temperature T) This zero energy level is used in physics. The rest state of a particle is hypothetical having the energy only due to the internal freedom of particles. We call the rest electron the vacuum electron, e< ao, and its energy the vacuum electron level, = 0. [Pg.8]

The rate of a cyclization reaction, thus its yield in competition with side reactions, is related to the probability of juxtaposition of the ends of the open-chain precursor. This probability increases with the configurational and conformational stability of the ring to be formed and decreases with increases in the loss of internal freedom that results from ring formation. ... [Pg.680]

It belongs to the point group CSince it is a nonlinear four-atomic molecule it has 3(4) -6 = 6 degrees of internal freedom. [Pg.334]

Such molecules have Td symmetry. As nonlinear, five-atomic species they have 3(5) -6 = 9 degrees of internal freedom. [Pg.335]

Such molecules belong to the point group Olt. They have 3(7) - 6 = 15 degrees of internal freedom. The 21 Cartesian displacement vectors generate the representation T given in the table below ... [Pg.337]

Humphreys and Hammett have estimated that in solution the entropy of acetic acid or its derivative is about 4-6 e.u. greater than the entropy of formic acid or its corresponding derivative due to the internal freedom of the methyl group. On this basis the authors concluded that the entropy of the acetate ion must be about the same as that of the formate ion, meaning that the internal motion of the methyl group is frozen out in the ionic species. It would appear from the data, however, that the entropy of the activated complex for acetate hydrolysis is more negative than that for formate hydrolysis by another 5 e.u. A possible explanation is that the charge becomes more concentrated in the acetate complex with a resultant increase in solvent electrostriction. [Pg.19]

Tim s urgent priority was therefore to arrange for as many people to take LSD as possible. His sensibility was basically religious, though the direction he moved in was political. Tim was out to change the State, his strategy being confrontation and his weapon a chemical substance which he called a sacrament. He vowed that in ten years a million Americans would win "internal freedom" (the Fifth Freedom, freedom to control one s central nervous system). [Pg.18]

Leary and associates tried in many ways to train people in the use of this drug, which they saw as a key to the "new age. Even before leaving Harvard, they established an off-campus organization known as IHF (the International Federation for Internal Freedom) and laid plans for an experiential LSD center on the beach at Zihuatanejo, Mexico. When they advertised this opportunity the next summer, IFIF received more than 1,500 applications. Leary requested 100 grams of LSD, about a million doses, and 25 kilograms of psilocybin, about 2 Vz million doses, from Sandoz, and sent a... [Pg.145]

This analysis in many ways parallels the theoretical treatment presented by Dafforn and Koshland [see Ref. (37)] as an extension and refinement of the initial proposal of orbital steering. They clearly established that the total effect could be large even after allowing for residual internal freedom in the transition state and that a loose complex as exemplified by bromine combination could occur with little loss of entropy. The point which is developed more fully here is that the microscopic model used for the statistical mechanical calculations is not the same macroscopic model used in the original definition of orbital steering. [Pg.20]

To account for the doublet character of the spectral lines of the alkali metals, it is necessary to introduce another degree of internal freedom to the atom. Goudschmidt and Uhlenbeck (1925) suggested this was electron spin, designated as the quantum number s (not to be confused with the term s electrons). The spin angular momentum is limited to the two values of h/2n, or s = , corresponding to opposite spins for the electron. [Pg.30]

For zeolitic adsorbents consisting of discrete cages interconnected through relatively small windows, Eq. (2.21) assumes a very simple form if the adsorbed species can be regarded as retaining complete translational, rotational, and internal freedom within the free volume of the cage ... [Pg.46]

This dimension is varied in limits 1internal freedom degree (mobility) of pointed chain part. The purpose of present paper is the application of a model [4] for deseription of deformability of carbon plastics based on the high density of polyethylene (HDPE). [Pg.26]

In certain biological applications of the halide probe technique, for example when a halide ion may be liganded to a Hg-label attached to a macromolecule, the halide ion at the binding site may experience a certain amount of internal freedom of motion with respect to the overall motion of the macromolecule. A schematic illustration of this situation is given in Fig. 8.1. [Pg.258]

This last expression indicates that there are two fundamental modes of motion belonging to the A irreducible representative and two fundamental modes of motion (one doubled or doubly degenerate) belonging to the E irreducible representation. Thus the total number of fundamental modes is 6, which is consistent with 3iV-6=3(4)-6=6 degrees of internal freedom. Now consider the character of the polarizability. Here the reduction expression becomes... [Pg.227]

The dynamic viscoelastic properties of the quenched polymers demonstrate the internal freedom and the high internal mobility of the mesomorphic structures at In fact, in the temperature interval... [Pg.70]


See other pages where Internal freedom is mentioned: [Pg.371]    [Pg.406]    [Pg.2]    [Pg.15]    [Pg.28]    [Pg.37]    [Pg.18]    [Pg.244]    [Pg.250]    [Pg.390]    [Pg.34]    [Pg.203]    [Pg.33]    [Pg.18]    [Pg.25]    [Pg.116]    [Pg.30]    [Pg.59]    [Pg.259]    [Pg.205]    [Pg.100]    [Pg.750]    [Pg.58]    [Pg.48]    [Pg.26]    [Pg.146]    [Pg.41]   
See also in sourсe #XX -- [ Pg.146 ]




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FIELDS AND INTERNAL DEGREES OF FREEDOM

Internal molecular degrees of freedom

Internal motional freedom

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Torsion angles, internal degrees freedom

Two Internal Rotational Degrees of Freedom

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