%0 Journal Article %T Tetramethylammonium hemi(terephthalate) dihydrate %A Yunxia Yang %A Laipeng Shi %J Acta Crystallographica Section E %D 2011 %I International Union of Crystallography %R 10.1107/s1600536811023312 %X In the title compound, (CH3)4N+¡¤0.5C8H4O42 ¡¤2H2O, the complete terephthalate dianion is completed by twofold symmetry and has a dihedral angle of 23.5 (2)¡ã between the carboxylate group and its parent ring. Two independent water molecules serve as both donors and acceptor in the construction of undulating hydrogen-bonded host layers with various O¡ªH...O contacts ocurring between the anion and two water molecules. At the same time, the tetramethylammonium cations, as the sphere-like guest species, are arranged in two rows between neighboring host layers, with an approximate interlayer distance of 7.36 , forming a sandwich-like crystal structure. %U http://scripts.iucr.org/cgi-bin/paper?S1600536811023312