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ARTICLE IN PRESS Ultramicroscopy 98 (2004) 145–150 Structural study of new hydrocarbon nano-crystals by energy-filtered electron diffraction a b c d a, b J.S. Wu , N. Melcer , W.P. Sharp , M. O’Keeffe , J.C.H. Spence *, O.M. Yaghi a Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1504, USA b Department of Chemistry, Materials Design and Discovery Group, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109, USA c Department of Plant Biology, Arizona State University, Tempe, AZ 85287-1504, USA d Department of Chemistry, Arizona State University, Tempe, AZ 85287-1504, USA Received 31 December 2002; received in revised form 16 April 2003 Dedicated to Professor Fang-hua Li on the occasion of her 70th birthday. Abstract A new brittle hydrocarbon has been successfully synthesized in polycrystalline form, and its crystal structure solved by quantitative electron diffraction. By 3D tilting of the nano-crystals, the lattice type and unit cell parameters were ( ( ( determined. (Triclinic, a ¼ 6:03 A, b ¼ 6:23 A, c ¼ 13:86 A, a ¼ 87:26 , b ¼ 106:69 , and g ¼ 119:01 .) Spot diffraction patterns were obtained at 165C using the Koehler selected-area mode on a LEO 912 TEM fitted with an omega in column elastic energy filter. The direct methods algorithm was then applied to merged