Cone angle factor

One simple way of quantifying steric effects in actinide complexes [the cone angle factor (caf) approach] uses the sum of the solid angles subtended by the ligands to the centre of the metal... 

The Pt—P (and Pt—Cl) bond lengths correlate with the electron-donating ability of the phosphine (Tolman s Xi factor) rather than steric factors (the cone angle of the tertiary phosphine) [150b]. 

My question to Dr. J. Kochi is whether it is possible to correlate the steric factor in his equations describing the oxidation of alkylmetal compounds to some measure of the bulkiness of the alkyl groups such as cone angles similar to ones suggested by Dr. C.A. Tolman for tertiary phosphine ligands. 

The penetration action of a shaped charge is dependent upon a number of factors, such as a)the explosive used, b)type of liner material and its thickness, c)cone angle and other shape of cavity and d)stmdr off distance or distance between the base of cavity and target. These factors must be determined experimentally for each explosive and for each type of shaped charge design... 

However, recently Pauldrach, Puls and Kudritzki (1986, "PPK") were able to prove that this failure of the theory was caused by one of the crucial approximations made by CAK, namely the "radial streaming approximation". In this approximation the interaction of photospheric photons with the wind plasma is treated as if they were streaming out radially from the stellar surface. This approximation is very poor. Even some stellar radii away from the star the photosphere forms a finite cone angle (Fig. 3), which is crucial for correct treatment of momentum exchange. This "finite cone angle effect" was taken into account by PPK by introducing a correction factor CF to the CAK radiative force fCA. ... 

Fig. 4 Finite cone angle correction factor to the radiative force as function of reciprocal radius (from Pauldrach et al., 1986).

Reasonable correlations of combustion efficiency with fuel spray momentum and spray energy in two different combustors have been shown to hold over a range of altitude-engine idling conditions 133). As different curves were obtained with different injector nozzles, spray-cone angle was thought to be a factor. Further work showed that efficiency did correlate closely with expressions representing the spray momentum or... 

The cone angles of optical isomers are, of course, identical, but it has been demonstrated that chiral phosphines in homogenous catalytic systems can determine a reaction pathway to form asymmetric products.199 Clearly the chirality of the phosphine is the determining factor in these systems, although other essential characteristics of the phosphine ligand s bulk and the it acidity still... 

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