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CH4 is Silicon tetrafluoride structured and crystallizes in the cubic I-43m space group. The structure is zero-dimensional and consists of two methane molecules. C4- is bonded in a tetrahedral geometry to four equivalent H1+ atoms. All C–H bond lengths are 1.10 Å. H1+ is bonded in a single-bond geometry to one C4- atom.
Based on optical microscopy and electron microprobe analyses, eight previously undescribed or poorly known chondrites were classified into compositional groups, petrologic types, and degree of shock alteration. These chondrites are: Leander, L4b; Nazareth(a), L6d; La Villa, H4b; Mereta, H4c; Gail, H4d; Shafter Lake, H5a; Uvalde, H5d; and Howe, H5d.