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INDEX triplet

Regardless of which tools were used in the indexing of the powder diffraction pattern, the most reliable solution should result in the minimum discrepancies in the series of simultaneous equations (Eq. 5.5 or its equivalent for a different crystal system) constructed with the observed 20 substituted into the left hand side and the assigned index triplets and refined unit cell dimensions substituted into the right hand side of each equation. While the minimum combined discrepancy is easily established algebraically, e.g. as the sum of the squared differences... [Pg.415]

We note that the benchmarks listed above must be applied altogether. For example, it is nearly always possible to choose the highest symmetry crystal system (i.e. cubic) and a large unit cell to dubiously assign index triplets to all observed Bragg peaks and obtain acceptable e. This happens because the density of points in the reciprocal lattice is proportional to the volume of the... [Pg.416]

It can be seen from equation (1.51) that the major difficulties in applying the HF CO method arise when calculating the two-electron integrals whose number is proportional to m for each upper (cell) index triplet (q, qi, q2). The method can be applied reasonably only if the three infinite sums in equations (1.48) and (1.51) can be truncated with a... [Pg.23]

By contrast, Fig. 9c shows an alternative scheme using linked list. In this scheme (scheme II) the information associated with a nonzero element is stored in a triplet containing the row index, the value of the nonzero element, and a pointer to the address of the next element in the same column. The starting addresses of each column are stored in another n locations. Notice that in this scheme the successive elements need not be stored in consecutive locations. To insert or delete an element requires only the change of one or two pointers no rearrangement of the list is necessary. On the other hand, the storage requirement for the same matrix is now 3 N + n and, as it stands, to find a specific nonzero element requires a linear search through the chain. [Pg.167]

The fluorescent components are denoted by I (intensity) followed by a capitalized subscript (D, A or s, for respectively Donors, Acceptors, or Donor/ Acceptor FRET pairs) to indicate the particular population of molecules responsible for emission of/and a lower-case superscript (d or, s) that indicates the detection channel (or filter cube). For example, / denotes the intensity of the donors as detected in the donor channel and reads as Intensity of donors in the donor channel, etc. Similarly, properties of molecules (number of molecules, N quantum yield, Q) are specified with capitalized subscript and properties of channels (laser intensity, gain, g) are specified with lowercase superscript. Factors that depend on both molecular species and on detection channel (excitation efficiency, s fraction of the emission spectrum detected in a channel, F) are indexed with both. Note that for all factorized symbols it is assumed that we work in the linear (excitation-fluorescence) regime with negligible donor or acceptor saturation or triplet states. In case such conditions are not met, the FRET estimation will not be correct. See Chap. 12 (FRET calculator) for more details. [Pg.346]

Fig. 1. Oxygen abundances as a function of the activity index, Rx, derived from X-ray data (left-hand panels) and the excitation temperature Texc (right-hand panels). The bottom panels show the difference between [O/Fe] yielded by the OI triplet at about 7774 A and the [OI] A6300 line. Filled circles RS CVn binaries ([2] and [3]), filled squares field subgiants [3], filled triangles Pleiades stars, open triangles Hyades stars, open circles, squares and hexagons disk dwarfs. The source of the literature data for the open cluster and Galactic disk stars can be found in [4]. Fig. 1. Oxygen abundances as a function of the activity index, Rx, derived from X-ray data (left-hand panels) and the excitation temperature Texc (right-hand panels). The bottom panels show the difference between [O/Fe] yielded by the OI triplet at about 7774 A and the [OI] A6300 line. Filled circles RS CVn binaries ([2] and [3]), filled squares field subgiants [3], filled triangles Pleiades stars, open triangles Hyades stars, open circles, squares and hexagons disk dwarfs. The source of the literature data for the open cluster and Galactic disk stars can be found in [4].
A large spin-donicity number is expected when the energy difference is smaller between the triplet and singlet states. Thus, spin-philicity and spin-donicity are also a measure of the energy differences between singlet and triplet states, furthermore, it has been demonstrated the applicability of these reactivity indexes in the prediction of the spin transfer observed in the spin-catalysis phenomenon [21], Equivalent quantities at fixed Ns ([Pg.150]

DN2Sy Triplet index from distance matrix, square of graph order ( of nonhydrogen atoms), and distance sum operation y — 1-5... [Pg.482]

ANly Triplet index from adjacency matrix, graph order, and number 1 operation y= 1-5... [Pg.482]

The phenanthrene/anthracene series is shown in Fig. 7 and the major peak in the m/z 234 trace has the retention index of retene which is generally derived from conifer wood burning. Sometimes there is a triplet of peaks in the same C4 plot due to benzonaphthothiophenes (C10H16S) which are components of some... [Pg.16]

As shown, for example, by calculations of the structural index A, the aromaticity of alumobenzene (112) is still lower than that in borabenzene. Calculations (MNDO) have shown the ground state of this molecule to be, in contrast to benzene, triplet (3B,). Even so, the 67r-electron structure of (112) is more stable than the 47r-electronic one. However, the difference between their energies (36.6 kcal/mol) is nearly twice as small as that for the corresponding structures of borabenzene. [Pg.360]

An overview of the energetics and possible depletion mechanisms of excited electronic states is named a Jablonski diagram. Herein, singlet states are symbolized by So, Si, S2, and so on, and triplets by T0, Ti, T2, and so on, where the index labels their energetic order and should not be confused with tensor components. A typical Jablonski diagram for an organic molecule is shown in Figure 19. [Pg.178]

Optical properties are usually related to the interaction of a material with electromagnetic radiation in the frequency range from IR to UV. As far as the linear optical response is concerned, the electronic and vibrational structure is included in the real and imaginary parts of the dielectric function i(uj) or refractive index n(oj). However, these only provide information about states that can be reached from the ground state via one-photon transitions. Two-photon states, dark and spin forbidden states (e.g., triplet) do not contribute to n(u>). In addition little knowledge is obtained about relaxation processes in the material. A full characterization requires us to go beyond the linear approximation, considering higher terms in the expansion of h us) as a function of the electric field, since these terms contain the excited state contribution. [Pg.58]

The resulting (sub)states are displayed in Fig. 11. The first state (Fig. 11a) is the triplet resulting from a n —> n single excitation, i.e., a ligand-centered (LC) triplet denoted as The upper left index corresponds to the spin multiplicity (25+1)... [Pg.215]

Figure 2.7. Dependence of the logarithm of relative parameters of the exchange interaction on the distance between the interacting centers (AR). krr is the rate constant of triplet-triplet electron transfer, and JSE is the spin-exchange integral. Index 0 is related to van der Waals contact. (Likhtenshtein, 1996) Reproduced in permission. Figure 2.7. Dependence of the logarithm of relative parameters of the exchange interaction on the distance between the interacting centers (AR). krr is the rate constant of triplet-triplet electron transfer, and JSE is the spin-exchange integral. Index 0 is related to van der Waals contact. (Likhtenshtein, 1996) Reproduced in permission.

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See also in sourсe #XX -- [ Pg.328 , Pg.329 , Pg.335 ]




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INDEX triplet lifetimes

INDEX triplet-singlet

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