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2-Phenylimidazolium hemi(benzene-1,4-dicarboxylate) trihydrate
The asymmetric unit of the title compound, C9H9N2
+.0.5C8H4O4
−·3H2O, contains one 2-phenylimidazolium cation, half a benzene-1,4-dicarboxylate anion and three water molecules, which are connected by O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional network
catena-Poly[[[bis[4-(1H-1,3,7,8-tetraazacyclopenta[l]phenanthren-2-yl)phenol-κ2 N 7,N 8]manganese(II)]-μ-naphthalene-1,4-dicarboxylato-κ2 O 1:O 4] naphthalene-1,4-dicarboxylic acid hemisolvate monohydrate]
The 1,4-dicarboxylate dianions in the title compound, [Mn(C12H6O4)(C19H12N4O)2]·0.5C12H8O4·H2O, bond to two 4-(1H-1,3,7,8-tetraazacyclopenta[l]phenanthren-2-yl)phenol-chelated Mn atoms to form a chain that features the metal atom in an octahedral coordination geometry. Adjacent chains interact with the uncoordinated water molecules to form a three-dimensional network. The naphthalene-1,4-dicarboxylic acid solvent molecule, which is disordered about a centre of inversion, occupies the space within the network but is not bonded to the network. One NH group is disordered equally over two positions
Divergence and Shannon information in genomes
Shannon information (SI) and its special case, divergence, are defined for a
DNA sequence in terms of probabilities of chemical words in the sequence and
are computed for a set of complete genomes highly diverse in length and
composition. We find the following: SI (but not divergence) is inversely
proportional to sequence length for a random sequence but is length-independent
for genomes; the genomic SI is always greater and, for shorter words and longer
sequences, hundreds to thousands times greater than the SI in a random sequence
whose length and composition match those of the genome; genomic SIs appear to
have word-length dependent universal values. The universality is inferred to be
an evolution footprint of a universal mode for genome growth.Comment: 4 pages, 3 tables, 2 figure
Poly[[μ4-naphthalene-1,4-dicarboxylato-κ4 O:O′:O′′:O′′′-μ2-naphthalene-1,4-dicarboxylato-κ4 O,O′:O′′,O′′′-bis(2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene-κ2 N 7,N 8)dimanganese(II)] N,N-dimethylformamide solvate]
One of the two 1,4-dicarboxylate dianions in the title compound, [Mn2(C12H6O4)2(C19H12N4)2]·C3H7NO, uses its two carboxylate groups to chelate two N-heterocycle-chelated Mn atoms; the other 1,4-dicarboxylate dianion binds to four such metal centers. The octahedrally coordinated Mn atoms are linked through the two dianions into a layer motif; the dimethylformamide molecules occupy the spaces between adjacent layers. Ten C atoms and attached H atoms of one dianion are disordered equally over two positions
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