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From separator calculation

Even within a particular approximation, total energy values relative to the method s zero of energy are often very inaccurate. It is quite common to find that this inaccuracy is almost always the result of systematic error. As such, the most accurate values are often relative energies obtained by subtracting total energies from separate calculations. This is why the difference in energy between conformers and bond dissociation energies can be computed extremely accurately. [Pg.8]

It may be shown that for the (0,1) sector of Fock-space, the values of the roots obtained by diagonalizing Hn s are independent of the active space used for the calculation. In other words, if two orbitals, a and b are taken as active, the resulting ionization potentials would be identical to those obtained from separate calculations with either a or 6 alone active. This is a very useful result because it means that we do not have to worry about choosing the right active space for a given calculation in order to get good results. However the proof of this invariance rests on the FSCC amplitudes and /7jv,eff satisfying the Fock-space Bloch equation 13. The approximate FSCCSDT methods described above do not satisfy Eq. 13, so the invariance is lost. [Pg.278]

For this purpose, we introduce orbitals of the type 4>g- and (f)g-which are obtained from separate calculations on the isolated systems A and B. The VB structures for A B are generated in the same way as for the AB system. It is clear that wavefunctions of the form d>A >B are optimal for describing AB, while are similarly sofor A B . In this last case, the... [Pg.382]

A more recent theory for the dynamic equilibrium drop diameter also started from separate calculations of the drop breakup and coalescence during the steady state shearing. The rate of particle generation was taken to be determined by microrheology, viz. Eq 7.52, [Huneault et al, 1995] ... [Pg.496]

Due to their simple structure, the core wavefunctions ls 2s and ls 2p P° were represented by HP wavefunctions. The basis set of bound orbitals and of the energy-normalized scattering orbitals, si and s t, were computed numerically from separate calculations via the term-dependent HE scheme. [Pg.384]

It has been shown that such electron dynamics can be performed in good agreement with time-resolved experiments for perylene-Ti02 interfaces with different anchor and spacer groups. In particular, the use of electronic structure information from previous atomistic quantum chemical calculations provides an illustration of a successful combination of different levels of theory into a first principles-based multiscale approach. Theoretical developments of such electron dynamics simulations have recently also included vibrational effects that can be incorporated from separate calculations of molecular vibrational modes. ... [Pg.117]

Equations (7-8) and (7-9) are then used to calculate the compositions, which are normalized and used in the thermodynamic subroutines to find new equilibrium ratios,. These values are then used in the next Newton-Raphson iteration. The iterative process continues until the magnitude of the objective function 1g is less than a convergence criterion, e. If initial estimates of x, y, and a are not provided externally (for instance from previous calculations of the same separation under slightly different conditions), they are taken to be... [Pg.121]

The values due to the two separate calculations are of the same quality we usually get from (pure) two-state calculations, that is, veiy close to 1.0 but two comments have to be made in this respect (1) The quality of the numbers are different in the two calculations The reason might be connected with the fact that in the second case the circle surrounds an area about three times larger than in the first case. This fact seems to indicate that the deviations are due noise caused by CIs belonging to neighbor states [e.g., the (1,2) and the (4,5) CIs]. (2) We would like to remind the reader that the diagonal element in case of the two-state system was only (—)0.39 [73] [instead of (—)1.0] so that incorporating the third state led, indeed, to a significant improvement. [Pg.711]

Carbon Dioxide—Water-Vapor Mixtures When these gases are present together, the total radiation due to both is somewhat less than the sum of the separately calculated effects, because each gas is somewhat opaque to radiation from the other in the wavelength regions 2.7 and 15 [Lm. [Pg.579]

Calculating the resistance of each current-carrying component separately is a very cumbersome and lengthy procedure, in addition to being not very accurate due to the large number of approximations. Some of the joints and components may still have been omitted from these calculations. The easier and more often recommended procedure is to measure the resistance between the extreme ends of each feeder in its ON condition by an Ohm-meter. This resistance will also include the contact resistance of each terminal and joint. [Pg.425]

The suction head or lift for the pump (separate calculation from NPSHa) is ... [Pg.191]

The exact procedure is to estimate a temperature profile from top to bottom of the column and then calculate a for each theoretical tray or stage by assuming a temperature increment from tray to tray. For many systems this, or some variation, is recommended to achieve good separation calculations. [Pg.25]

The outer and inner tubes extend from separate stationary tube sheets. The process fluid is heated or cooled by heat transfer to/from the outer tube s outside surface. The overall heat transfer coefficient for the O.D. of the inner tube is found in the same manner as for the double-pipe exchanger. The equivalent diameter of the annulus uses the perimeter of the O.D. of the inner tube and the I.D. of the inner tube. Kem presents calculation details. [Pg.239]

In fact, a measure of the degree of confidence can be gained from the t calculation. Shown in Appendix A are columns for greater degrees of confidence. The value for df = 4 for a 98% confidence level is 3.747 and it can be seen that the experimentally calculated value is also greater than this value. Therefore, the level of confidence that these samples came from different populations is raised to 98%. However, the level of confidence in believing that these two samples came from separate populations does not extend to 99% (t = 4.604). Therefore, at the 98% confidence level this analysis indicates that the potency of human calcitonin is effectively increased by enrichment of G -protein in the cell. [Pg.228]

Photoelectric-Colorimetric Method. Although the recording spectrophotometer is, for food work at least, a research tool, another instrument, the Hunter multipurpose reflectometer (4), is available and may prove to be applicable to industrial quality control. (The newer Hunter color and color difference meter which eliminates considerable calculation will probably be even more directly applicable. Another make of reflection meter has recently been made available commercially that uses filters similar to those developed by Hunter and can be used to obtain a similar type of data.) This instrument is not a spectrophotometer, for it does not primarily measure the variation of any property of samples with respect to wave length, but certain colorimetric indexes are calculated from separate readings with amber, blue, and green filters, designated A, B, and G, respectively. The most useful indexes in food color work obtainable with this type of instrument have been G, which gives a... [Pg.9]

Table 23. Enthalpies of formation AHj (kj mol-1) in the gas phase (g) and in dichloro methane solution (s) calculated from separate molecules at selected points of the C4H9BF4 potential energy hypersurface... Table 23. Enthalpies of formation AHj (kj mol-1) in the gas phase (g) and in dichloro methane solution (s) calculated from separate molecules at selected points of the C4H9BF4 potential energy hypersurface...
Na (g) + Cl (g) NaCK. ) A -calculated - - 769 kJ/mol This Is the energy released when the solid forms from separated gaseous ions. The reverse process, in which an ionic solid decomposes into gaseous ions, is termed the lattice energy (LE) and is a positive quantity ... [Pg.547]

Data from several laboratories within the Interregional Research Project No. 4 (IR-4) in the USA have been evaluated for determining the values of MDL and MQL. These data have been presented in Table 1. The two-step procedure described in the EPA guideline was used to calculate the values of MDL and MQL. For the first step, the slope, intercept and RMSE values for the first three calibration curves of each study were separately calculated, then the IDL and IQL values calculated and the value of LQQ estimated for the method. These values were compared with the actual values of LLMV. The standard deviation of the spike recoveries at the LLMV (xllmv) was used to calculate the MDL and MQL. The values of LLMV were separately determined by the laboratory not using any of the methods described in this article. [Pg.73]

Their q-values, either calculated from the experimental conditions or chosen for best fit, and their corresponding relaxation rate constants, obtained from separate stress-jump experiments, are listed in Table III. [Pg.199]


See other pages where From separator calculation is mentioned: [Pg.178]    [Pg.154]    [Pg.178]    [Pg.154]    [Pg.125]    [Pg.51]    [Pg.623]    [Pg.14]    [Pg.258]    [Pg.1834]    [Pg.145]    [Pg.197]    [Pg.130]    [Pg.130]    [Pg.23]    [Pg.63]    [Pg.149]    [Pg.93]    [Pg.326]    [Pg.163]    [Pg.210]    [Pg.62]   
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