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Inertia calculation

For moment of inertia calculations, to approximate the effect of roof cracking due to out-of-plane loads, use half the roof slab thickness. [Pg.82]

Bertka and Fei (1997) experimentally determined mantle mineral stabilities using the Wanke and Dreibus (1988) model composition. The mineral stability fields and resulting mantle density profile, as well as core densities and positions of the core-mantle boundary for a range of model core compositions, are illustrated in Figure 9. The moment of inertia calculated from these experimental data (0.354) is consistent with the Mars Pathfinder measurement (Bertka and Fei, 1998). However, this model requires an unrealistically thick crust. [Pg.604]

The molecular constants, bond distance, and bond angle were determined by electron diffraction by Pinbak et al. (2, ). The constants reported by Pinbak et al. (3 ) in 1943 were selected. These constants are listed in "Tables of Interatomic Distances and Configuration in Molecules and Ions," Special Publication No. 11, The Chemical Society (London), 1958. The principal moments of inertia calculated from these constants are B C " 10 g cm. ... [Pg.550]

The adopted molecular structure data are from the electron diffraction study of Brockway and Cross (12) which conclusively indicates a tetrahedral structure. Moment of inertia calculations based on the adopted bond distances and angles yield -38 2... [Pg.680]

Individual moments of inertia calculated from the structural data given above are --39 2... [Pg.1123]

The vibrational frequencies are from the infrared studies of Selig and Claasen ( ) and are in good agreement with the Raman and infrared studies of Gutowsky and Liehr (4). Several microwave studies (5, 6, 7, 8) of POFg have been reported. As pointed out by Williams et al. (7), the rotational constant calculated from their microwave studies leads to a moment of inertia, Ig, which is in disagreement with the moment of inertia calculated from the molecular constants obtained from electron-diffraction studies by Brockway and Beach (9). Since insufficient microwave data were available for an independent determination, Williams et al. (7 ) sought to find parameters which were consistent with both measurements. Their molecular constants are adopted for this tabulation. Individual moments of inertia are I... [Pg.1124]

The moment of inertia of the whole system, /, is determined using an additional ring of the known moment of inertia calculated from the equation... [Pg.377]

The second common type of operationally defined structure is the so-called substitution or rt structure.10 The structural parameter is said to be an rs parameter whenever it has been obtained from Cartesian coordinates calculated from changes in moments of inertia that occur on isotopic substitution at the atoms involved by using Kraitchman s equations.9 In contrast to r0 structures, rs structures are very nearly isotopically consistent. Nonetheless, isotope effects can cause difficulties as discussed by Schwendeman. Watson12 has recently shown that to first-order in perturbation theory a moment of inertia calculated entirely from substitution coordinates is approximately the average of the effective and equilibrium moments of inertia. However, this relation does not extend to the structural parameters themselves, except for a diatomic molecule or a very few special cases of polyatomics. In fact, one drawback of rs structures is their lack of a well-defined relation to other types of structural parameters in spite of the well-defined way in which they are determined. It is occasionally stated in the literature that r, parameters approximate re parameters, but this cannot be true in general. For example, for a linear molecule Watson12 has shown that to first order ... [Pg.72]

Optimized geometries, harmonic vibrational frequencies and moments of inertia calculated at the B3LYP/6 -31 lG(d,p) level of Density Punchonal Theory are reported in Appendix B. [Pg.89]

It has been shown for diatomic molecules that the parameter is a single average of the r-Q and parameters. This relation holds only approximately, or may even fail, for polyatomic molecules. However, Watson [24] demonstrated that, if higher-order terms were neglected in the expansion of moments of inertia in terms of the isotope mass difference, the equihbrium moment of inertia was approximately given by 2/s-/o, where denoted the moment of inertia calculated using coordinates. [Pg.8]

Morino et al. converted their electron diffraction rg distances into in order to compare the moments of inertia calculated from r (denoted 7 ) with the spectroscopic Ix, calculated by correcting Maid s values to Bx. The results are summarized in Table 5. Here the errors in the electron... [Pg.186]

Restricted Internal Rotation of Several Symmetric Tops. The tables of thermodynamic functions for an internal rotation of a single symmetric top may be used for several symmetric tops [with moments of inertia calculated from equation (20)] provided both potential energy and kinetic energy cross-terms between the tops can be neglected. Both assumptions have been generally made in calculations for molecules with several tops. Where there are reliable calorimetric data at one or more temperatures, the tables have been used to calculate appropriate potential barriers. Using this procedure thermodynamic contributions have been calculated for propane, 2-methylpropane, 2,2-dimethylpropane, cis-but-2-ene, rm a -but-2-ene, isobutene, o-xylene, > m-xylene, p-xylene, 1,2,3-trimethylbenzene, > 1,2,4-trimethylbenzene, dimethyl sulphide,2-chloro-2-methylpropane, and dimethyl-amine. In several cases thermodynamic contributions have been calculated using potential barriers estimated from those of related molecules. Examples of this procedure are found in calculations for 2-fluoro-2-methylpropane, 2-chloropropane, 2-bromopropane, 2-iodopro-pane, 2,2-dichloropropane, 2-bromo-2-methylpropane, 2-iodo-2-methylpropane, 1,3,5-trimethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, 1,2,3,4-tetramethylbenzene, pentamethyl-benzene, and hexamethylbenzene. ... [Pg.288]

Wire diameter in the installation was chosen equal to 6x 10" m. Thus, the polar moment of inertia calculated by the formula above makes 1272x10 m"", suspension length is 2.5 m. [Pg.305]

TABLE 6.2,2/ Entrance Pressure Drop from Figure 6.2.11 Compared to Inertia Calculation... [Pg.252]

The bond distances in H2O are equal to 95.8 pm, and the bond angle is equal to 104.45°. Find the location of the center of mass and the principal moments of inertia. Calculate the rotational partition function at 298.15 K. Don t forget the symmetry number. [Pg.1076]

Here [7°]i (g = 1) is the ground-state moment of the parent isotopic species and [7 ]i is the substitution moment of inertia calculated from the set of substitution coordinates of the parent species. The dataset, the L isotopic species, is that needed for evaluation of a complete substitution structure. For a linear XYZ molecule, four isotopic species (including the parent) are needed for the substitution structure. From Eqs. (99) and (98), it follows for the parent, g = 1, that [7 ]i = 7 . The rationale for... [Pg.320]


See other pages where Inertia calculation is mentioned: [Pg.73]    [Pg.41]    [Pg.557]    [Pg.1126]    [Pg.1156]    [Pg.40]    [Pg.121]    [Pg.196]    [Pg.201]    [Pg.385]    [Pg.12]   
See also in sourсe #XX -- [ Pg.36 ]




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