Methyl fl-cellobioside-methanol (C13OI1H24.CH3OH) has space group P21 with two molecules per unit cell. The lattice parameters are a=7.652, b=25.532, c=4.496 A, and fl= 101"84 ° at the experimental temperature of about -193°C. The structure was solved by means of the symbolic addition technique and Fourier syntheses. Block-diagonal least-squares refinement resulted in a final R index of 0"060 for 1724 reflections. The C(5)-C(6) and C(5')-C(6") bonds are shorter than the average carboncarbon bond in the corresponding glucopyranose rings by 2.2 and 3.0 a. The C(I)-O(1) and C(I')-O(I') equatorial glycosidic bonds are shorter than the average of the carbon-hydroxyl bonds by 7.2 and 9.3 a. The valence angle at the O(1') oxygen atom is 2.7 ° smaller than that of the O(1) oxygen atom. The structure contains a bifurcated intramolecular hydrogen bond between the two glucopyranose rings. The angle of twist between the least-squares planes formed by the two rings is 169.3 °. The ring-to-ring conformation after Rees & Skerrett is (-25 °, + 142°). The average deviation between the carboncarbon, ring oxygen-carbon, and glycosidic oxygen-carbon bond lengths which are common to methyl /%cellobioside and cellobiose is 0-005 A.

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The reactions of the system were induced by light of wavelength 365-366.5 µ. The products of the system were removed from the reactor and dissolved in water. The water solution was tested for the ionic chlorine species chloride, hypochlorite, chlorite, chlorate, and perchlorate. Dichlorine heptoxide was found to be the only stable chlorine oxide product of the reaction. The formation of dichlorine heptoxide was studied with respect to the light intensity, reactant concentration, presence of diluents, temperature, and total pressure. The observed data and information already in the literature were used to develop a reaction mechanism which was based on the formation of a proposed chlorine atom-ozone complex. Analysis of the mechanism showed that it adhered to the observed data and the use of certain known rate constants allowed the attainment of several rate constants concerning the formation of the chlorine atom-ozone complex.

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Articles you may be interested in Theoretical studies of the reaction dynamics of the matrix-isolated F2+c i s-d 2-ethylene system J. Chem. Phys. 95, 8901 (1991); 10.1063/1.461223 Picosecond photofragment spectroscopy. II. The overtone initiated unimolecular reaction H2O2(v OH=5)→2OH J. Chem. Phys. 87, 97 (1987); 10.1063/1.453529 Picosecond photofragment spectroscopy. I. Microcanonical state-to-state rates of the reaction NCNO→CN+NO P~~osecond photofragment spectroscopy of the ultraviolet (UV) photodissociation of 1,2-duodotetrafluoroethane reveals consecutive breaking of the two C-1 bonds. Spin-orbit excited (I*) atoms show a prompt rise, in agreement with a direct mode dissociation of the first bond. Gr~und-state (I) atoms show a biexponential buildup, one component being fast (.;;;; 1 ps) whtle the other component is slow (30-150 ps depending on total energy), characteristic of the second bond breaking. The transient behavior ofl atoms changes with the available energy. These results are interpreted in terms of a two step model involving a weakly bound radical. Simulations of transient behavior of I atoms, based on estimated internal energy distributions from the pri~ary step and a model for dissociation rates as a function of energy, suggest that surface crossmgs are relevant to the dynamics and that the quantum yield of I atoms varies with excitation energy.