Q transitions

Some caveats about the form presented for the rate law (Eqn. 16.2) are worth noting. First, although Equation 16.2 is linear in Q , transition state theory does not demand that rate laws take such a form. There are nonlinear forms of the rate... 

Nuclear transition probabilities are also influenced by the quadrupole interaction, e.g. for 2 hfs — 2 q transitions with Ami > 1 may be induced. Nitrogen ENDOR spectra with Ami = 2 transitions have been observed in several metal complexes with small 14N hf couplings59,70,715. 

The electronic absorption spectrum of nickelocene has been recorded and analyzed in considerable detail by Scott and Becker.11 They found band maxima at 1920, 3075, and 6920 A and shoulders at 2700, 3450, 4400, and 5700 A. The band at 1920 A is believed to be an allowed transition which is designated as a W-F transition in ferrocene, but the intensity of this band is less than the N-V band in ferrocene. The shoulder at 2700 A is denoted as a N-Vor N-Q transition similar to the 2300 and 2600 A shoulders in ferrocene. The band at 3075 A is relatively intense and occurs at approximately the same wavelength as the intermolecular charge transfer band of ferrocene in carbon tetrachloride described by Brand and Snedden. The absorption spectrum of nickelocene in carbon tetrachloride shows no new bands other than those found in cyclohexane or ethanol. 

Interestingly, at the higher temperatures and if low densities are employed, the Q branch has a minumum near the Q ) transition frequency at 4155 cm-1, and there are two maxima (in the early days of collision-induced absorption, these were called the Qr and Qp lines ) these and the resulting dip between the maxima are clearly visible in the high-temperature spectra, Fig. 3.31. These maxima have a frequency separation... 

Intercollisional dip. In most examples of the rotovibrational spectra shown, one notices a fairly well developed dip at the Q transition frequency. 

Fig. 2 Spectra of y-rays coincident with the E0q+ q+ transition in 196Pb.

Fig. 2.2. Isometric projections of probability density pb(0,

Comparing Fig. 3.6(a) and 3.6(6) we see that in both situations anisotropy with respect to M" is created in the form of alignment, since = mean value of the projection of the angular momentum upon the quantization axis equals zero. There is, however, a substantial difference. For a Q-transition, mainly the sub-levels in the vicinity of M" = 0 are populated, see Fig. 3.6(a) (bottom), whilst the level M" = 0 itself is not depopulated, as follows from (3.10). 

The possibility of optical alignment by absorption of angular momenta in the ground state of a molecule was first demonstrated by Drullinger and Zare [124] in 1969. The authors used the Q-transition (X1S =... 

As one can see from Fig. 3 (the spectral dependence of optical conductivity u(e) in the interval of interband transitions) the greatest changes are observed for the high-frequency conductivity, caused by yi > q (/ > /, ) transition [9-10], This... 

Around 1.98 A, it will overcome small energy barriers generated by avoided crossing between the bound 1 A and 1 A" states and the repulsive 3A and 5A" upper states calculated at 2.88 and 2.87 eV, respectively and corresponding to MLCT (dpe tt q) transitions. A refined treatment of the potentials leading to a more realistic relative position of the electronic ground state and Q-band lA, lA" potential wells should confirm this mechanism and explain the observed timescale of dissociation (50 fs) characteristic of a direct ultrafast process. ... 

Inverted micellar cubic phases have been observed mainly in mixtures of double-chain polar lipids with fatty acids or diacylglycerols but also in some single-component dispersions of glycolipids (61). The most frequently observed inverted micellar cubic phase in lipids is of space group Fd im). For medium-chain lipids (>16C atoms), it typically forms via an Hn-Q transition however, the Lp gel phase of diC19-xylopyranosyl has been found to melt directly into the Fd im cubic phase (61). 

Zeeman shift required a careful analysis, so that also the 2 P, Gj was measured. V. Hughes and collaborators measured all the three intervals separately, since the mixing of FS levels induced by the magnetic fields allowed even 7 = 2 to J = Q transitions (we note as. J a. level that connect to the J manifold at zero magnetic field). Their published results have been recently modified by taking into account better the systematic effects due to the strong magnetic fields [12]. 

Q —> m + Q (transition to ground state) (through intersystem crossing)... 

Fig. 3. Numerical calculated position and intensities of the pure rotational spectrum of dipolarly unstable tetrahedral systems for the following parameter values (in inverse centimeters) A = 0.5, B = 5.24, kT = 200. Marked with crosses and circles and unmarked are the R, R", and R branches, respectively, with the Q transition indicated by an arrow (p is the gas pressure in amagat units).

---