Ethane crystal structure

Fernandez, E.J., Gimeno, M.C., Jones, P.G., Laguna. A.. Laguna, M. and Olmos, E. (1996) Synfiiesis of heteropolynudear complexes with 1,1,1-tris (diphenylphosphinomethyl)ethane. Crystal structure of [(OC)4Mo (Ph PCHJjCMelCHjPPhjDAuCl). Journal of the Chemical Society, Dalton Transactions, (17), 3603—3608. 

It is seen from Table 11-2 that the ethane crystal structure is reproduced to within 60 per mille in unit cell dimensions. Note that the two potential energy functions were developed for free molecules. Both will be acceptable candidates for optimisation, but should not be used in general in their present form. 

Quite recently, Ciampolini and coworkers have reported the synthesis of two isomeric mked oxygen-phosphorus macrocycles and the crystal structures of their cobalt complexes. Synthesis of macrocycle 27 was accomplished by condensation of 1,2-bis-(phenylphosphino)ethane dianion with 2,2 -dichlorodiethyl ether in THE. The two isomers of 27 were isolated in 1.5% and 2% yield. The synthesis is formulated in Eq. (6.17), below. 

In 1986, Walz and Haase [148] presented the crystal structure of the mesogenic hydrocarbon compound l,2-bis-(4 -pentylcyclohexyl)ethane. The compound exhibits a smectic B phase over a remarkably broad range of temperature. To our knowledge, this is the only crystal structure determination of a mesogenic hydrocarbon compound up to now. Since this compound does not contain any polar groups, the arrangement in the crystalline state is... 

Fig. 26. Crystal structure of l-(4 -cyanophenyl)-2-(4 -pentylcyclohexly)ethane along the c-...

The reaction of P4X3 (X = S, Se) with [IrCl(cod)]2 in the presence of triphos (triphos= 1,1, l-tris((diphenylphosphino)methyl)ethane) yields the compounds [(triphos)Ir(P3X3)] CV,I I f, according to Reaction Scheme 38.607 The crystal structure of X = S shows that the compounds contain the (triphos)Ir moiety replacing a basal P atom of the cage. 

Working first with Polanyi, Weissenberg, and Brill, and later as the leader of the Textile Chemistry Section, Mark successively published papers on the crystal structures of hexamethylenetetramine, pentaerythritol, zinc salts, tin, urea, tin salts, triphenylmethane, bismuth, graphite, sulfur, oxalic acid, acetaldehyde, ammonia, ethane, diborane, carbon dioxide, and some aluminum silicates. Each paper showed his and the laboratory s increasing sophistication in the technique of X-ray diffraction. Their work over the period broadened to include contributions to the theories of atomic and molecular structure and X-ray scattering theory. A number of his papers were particularly notable including his work with Polanyi on the structure of white tin ( 3, 4 ), E. Wigner on the structure of rhombic sulfur (5), and E. Pohland on the low temperature crystal structure of ammonia and carbon dioxide (6, 7). The Mark-Szilard effect, a classical component of X-ray physics, was a result of his collaboration with Leo Szilard (8). And his work with E. A. Hauser (9, 10, 11) on rubber and J. R. 

The largest number of hydrogen bonds in crystal structures of alkyl hydroperoxides refer to intermolecular bonds between the hydroperoxide proton and functionalities of the type 0=X, where X denotes a sulfur (e.g. 27), carbon (e.g. 30) or a phosphorous atom (e.g. 32, Figure 14, Table 7)93,108,115 geometry of [l,2-bis(diphenylphosphinoyl)ethane] bis(2,2-dihydroperoxypropane) (32) in the solid state is a rare example of a bifurcated hydrogen bond between an OOH donor and an 0=X proton acceptor. 

Bidentate diphosphines, such as bis(diphenylphosphino)methane (dppm) [242— 244], l,2-bis(diphenylphosphino)ethane (dppe) [245], l,2-bis(hydroxymethylpho-sphinojethane (hmpe) [246], l,2-bis(dicydohexyphosphine)ethane (dcype) [247] or bis(diphenylphosphino)isopropane (dppip) [248] build structures of stoichiometry [Au2(P P)2]2+ such as those shown in Figure 2.45. The crystal structure of [Au2(dmpe)2]X2-nH20 (dmpe = l,2-bis(dimethylphosphino)ethane X = Cl, n = 2 Br, = 1.5) consist of polymeric chains anion/water molecule/cation/anion/cat-ion/anion/water molecule [249]. 

The above findings are analogous to those reported by the same research group for ethane (Morita et al., 2000) and ethylene (Sugahara et al 2000) hydrates. Based on Raman spectroscopy, ethane or ethylene occupancy of the small cavities of structure I increases with increasing pressure. The low small cage occupancy of ethane in structure I hydrate was also detected from single crystal x-ray diffraction measurements (Udachin et ah, 2002). 

The accuracy of the A vsi-value method is impressive, considering the fact that the method preceded the knowledge of the crystal structure. Carson and Katz (1942) labeled their charts as tentative, yet the original methane, ethane, and propane charts continue to be useful. The KVS1 chart of methane was constructed from three data points at 4.14 MPa (600 psia), while the curves at other pressures were based on two data points and drawn symmetrically to the curve at 4.14 MPa (Katz, D.L. Personal Communication, November 14, 1983). 

It should be thermodynamically impossible for one set of Kvst charts to serve both hydrate structures (si and sll), due to different energies of formation. That is, the Kysi at a given temperature for methane in a mixture of si formers cannot be the same as that for methane in a mixture of sll formers because the crystal structures differ dramatically. Different crystal structures result in different xst values that are the denominator of Kvst (= yt/xSi). However, the Katz Kvst charts do not allow for this possibility because they were generated before the two crystal structures were known. The inaccuracy may be lessened because, in addition to the major component methane, most natural gases contain small amounts of components such as ethane, propane, and isobutane, which cause sll to predominate in production/transportation/processing applications. 

The planar ethylene (C2H4) molecules form a different type of crystal structure than that for ethane. As shown in Figure 11.6, the structure is body-centered [3 2PTOT(o)l with two molecules in the orthorhombic unit cell, D j, Pnnm, a0 = 4.87, b0 = 6.46, c0 = 4.14 A. The cell is elongated along b0 because the C=C bonds are skewed in two orientations in this direction. The orientation of the C=C bond in the molecule in the center of the cell differs from those at the comers. The C=C bond length is 1.33 A. 

Power, K. N., Hennigar, T. L., Zaworotko, M. J., X-ray crystal structure of Cu[l,2-bis(4-pyridyl)ethane]2(N03)2 n the first example of a coordination polymer that exhibits the NbO 3D network architecture. Chem. Commun. 1998,... 

Preparative studies and luminescence studies have been conducted on the diphosphine derivative trans-02Re(dmppe)2+, including an X-ray crystal structure of this complex (dmppe is l,2-Ms(di-4-methylphenylphosphino)-ethane) [20]. The complex excited state emits both in the solid state and in CH3CN solution with a 1.1 us lifetime in the solid. The emission energy is... 

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