caa a22 4500 46318453X CHVBK 20180406164848.0 cr unu---uuuuu 170326e20070301xx s 000 0 eng 10.1007/s10870-006-9129-x doi (NATIONALLICENCE)springer-10.1007/s10870-006-9129-x Conformational diversity: Six conformers side-by-side in the crystal cell of 2,2′,7,7′-tetramethoxy-9,9′-spiro-9-silabifluorene [Elektronische Daten] [I. Karle, R. Butcher, M. Wolak, S. Lee, Z. Kafafi] X-ray crystal structure analysis of a sublimation-grown spiro silabifluorene, that is highly fluorescent in the violet-blue, established that there are six cocrystallized ordered conformers in the asymmetric unit. Crystals were grown by a vapor transport method under argon gas flow at temperatures between 255-280°C. As expected, there are no cocrystallized solvent molecules. There is no π-stacking of the aryl groups. There is no possibility for normal hydrogen bond formation; however, several CH⋯π bonds occur. The packing is efficient with a density of 1.24g/cc. Each conformer deviates from tetrahedral geometry around the Si atom. Cell data are: C28H24O4Si×12, sp. gr. P $\bar 1$ , a=16.2750(5)Å, b=20.6613(5)Å, c=23.8289(5)Å, α=102.025(2)°, β=94.252(2)°, and γ=109.916(2)°, V=7275(1)Å3. Springer Science+Business Media, Inc., 2007 approximately orthogonal moieties nationallicence high temperature crystal form nationallicence π-stacking nationallicence hydrogen bonding nationallicence planar fluorene groups nationallicence pseudo-centers of symmetry nationallicence spiro-silabifluorene derivative nationallicence Karle I. Laboratory for the Structure of Matter, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut Butcher R. Chemistry Department, Howard University, 525 College Street, 20059, N.W. Washington, DC, USA aut Wolak M. Optical Sciences Division, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut Lee S. Optical Sciences Division, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut Kafafi Z. Optical Sciences Division, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut Journal of Chemical Crystallography Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 37/3(2007-03-01), 171-179 1074-1542 37:3<171 2007 37 10870 https://doi.org/10.1007/s10870-006-9129-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10870-006-9129-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Karle I. Laboratory for the Structure of Matter, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut NATIONALLICENCE 700 1- Butcher R. Chemistry Department, Howard University, 525 College Street, 20059, N.W. Washington, DC, USA aut NATIONALLICENCE 700 1- Wolak M. Optical Sciences Division, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut NATIONALLICENCE 700 1- Lee S. Optical Sciences Division, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut NATIONALLICENCE 700 1- Kafafi Z. Optical Sciences Division, Naval Research Laboratory, 20375-5341, Washington, DC, USA aut NATIONALLICENCE 773 0- Journal of Chemical Crystallography Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 37/3(2007-03-01), 171-179 1074-1542 37:3<171 2007 37 10870 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer