Cyclohexane Neopentane

Figure 16 Variation of kjk-o with in condensed nonpolar media [99,100,112]. Neopentane, liquid (A) and solid (A) neohexane (t) TMS (V) w-pentane, w-hexane ( + ) w-hexane, cyclohexane ( ) neopentane-w-hexane mixtures (x) methane, liquid ( ) and solid ( ) and argon, liquid (O) and solid...

Graphical method for calculating v of the mixture cyclohexane-neopentane at 273.2 K... 

It appears from Fig. 11.4.5 that the theorem of corresponding states is wdl satisfied. If we had here /) = 0, the grapliical method would be very simple. For example, for cyclohexane-neopentane... 

Investigation of Ethane, Propane, Isobutane, Neopentane, Cyclopropane, Cyclopentane, Cyclohexane, Allene, Ethylene, Isobutene, Tetramethylethylene, Mesitylene, and Hexamethylbenzene. Revised Values of Covalent Radii (by Linus Pauling and L. O. Brockway)... 

Fig. 12.4. Vapor-to-water transfer data for saturated hydrocarbons as a function of accessible surface area, from [131]. Standard states are 1M ideal gas and solution phases. Linear alkanes (small dots) are labeled by the number of carbons. Cyclic compounds (large dots) are a = cyclooctane, b = cycloheptane, c = cyclopentane, d = cyclohexane, e = methylcyclopentane, f = methylcyclohexane, g = cA-l,2-dimethylcyclohexane. Branched compounds (circles) are h = isobutane, i = neopentane, j = isopentane, k = neohexane, 1 = isohexane, m = 3-methylpentane, n = 2,4-dimethylpentane, o = isooctane, p = 2,2,5-tri-metbylhexane. Adapted with permission from [74], Copyright 1994, American Chemical Society...

Figure 15 Variation of k,- with /

Figure 8 Connection between primary C-H and C-C bond ruptures during radiolysis and photolysis. Alkanes (1) propane, (2) w-butane, (3) -pentane, (4) -hexane, (5) w-heptane, (6) n-octane, (7) w-decane, (8) isobutane, (9) neopentane, (10) 3-methylpentane, (11) 2,2-dimethylbutane, (12) isooctane, (13) cyclopentane, (14) cyclohexane, (15) cycloheptane, (16) cyclooctane, (17) cyclodecane, (18) methylcyclopentane, (19) methylcyclohexane, (20) ethylcyclohexane, (21) 1,1-dimethylcyclohexane, (22) cis-l,2-dimethylcyclohexane, (23) fraw5-l,2-dimethylcyclohexane, (24) cis-1,3-dimethylcyclohexane, (25) trarw-l,3-dimethylcyclohexane, (26) cw-l,4-dimethylcyclohexane, (27) trawi-l,4-dimethylcyclohexane. (From Refs. 18, 29, 91, 92, 99, 100, 108, 110, 111, 113, 114, and 160.)...

No single model can exactly describe molecular reorientation in plastic crystals. Models which include features of the different models described above have been considered. For example, diffusion motion interrupted by orientation jumps has been considered to be responsible for molecular reorientation. This model has been somewhat successful in the case of cyclohexane and neopentane (Lechner, 1972 De Graaf Sciesinski, 1970). What is not completely clear is whether the reorientational motion is cooperative. There appears to be some evidence for coupling between the reorientational motion and the motions of neighbouring molecules. Comparative experimental studies employing complementary techniques which are sensitive to autocorrelation and monomolecular correlation would be of interest. 

In this section, we shall examine the results which have been obtained for the exchange of the saturated hydrocarbons methane, ethane, cyclopentane, cyclohexane, cycloheptane, cyclo-octane, and neopentane. The common characteristic of this group is that all the carbon-hydrogen bonds in each individual molecule are similar in nature. An attempt will be made to indicate how the results fit into the classifications outlined in Sec. II. 

The pulse radiolysis studies of liquid alkanes have relevance to the radiolysis of polyethylene and related polymers. In liquid alkanes at ambient temperature, the reaction intermediates such as alkane radical-cations, olefin radical-cations, olefine dimer-cations, excited states, and alkyl radicals have been observed after the electron-pulse irradiation [90-93]. According to the nanosecond and subnanosecond studies by Tagawa et al., the observed species were alkane radical cations, excited states, and alkyl radicals in n-dodecane excited states and cyclohexyl radical were observed in cyclohexane, and only radicals in neopentane [91, 93]. Olefin radical-cations were also detected in cyclohexane containing carbon tetrachloride [92],... 

Of the medium pore structures (11,31,41), only the 11 structure has been published (22,25) and it has parallel, elliptical, non-intersecting 10-ring channels. Adsorption data indicate that cyclohexane is readily adsorbed but neopentane is excluded. The other two structures show less differentiation between cyclohexane and neopentane and may, in fact, have elliptical 12-ring pores. 

Hoyano JK, Graham WAG. Oxidative addition of the carbon-hydrogen bonds of neopentane and cyclohexane to a photochemically generated iridium(I) complex. J Am Chem Soc 1982 104(13) 3723-3725. 

J. K. Hoyano, and W. A. G. Graham, Oxidative Addition of the Carbon-Hydrogen Bonds of Neopentane and Cyclohexane to a Photochemically Generated Iridium(I) Complex, J. Am. Chem. Soc. 104, 3723-3725 (1982). 

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