Nitroethane at high density: an experimental and computational vibrational study

Raman and IR vibrational spectra confirm two molecular units associated with the monoclinic unit cell of nitroethane under high pressure. Raman spectra are extremely sensitive to predicted effects of unit cell distortion due to changes in H-bonding.

Terrywallaceite from the Kochkar Au Deposit, South Urals: First Find in Russia

Terrywallaceite, AgPb(Sb,Bi)3S6, a rare sulfosalt of the lillianite homologous series, was found in a sample from the Kochkar Au deposit (Chelyabinsk oblast). It occurs as anhedral grains up to 0.4 × 0.3 mm and is associated with Sb-bearing bismuthinite, tetrahedrite-(Fe), arsenopyrite and minerals of the tintinaite–kobellite series. Its average empirical formula based on eight analyses is as follows: (Ag0.97Cu0.07)Σ1.04(Pb0.94Cd0.02)Σ0.96(Bi1.84Sb1.17)Σ3.01(S5.99Se0.01)Σ6.00.The monoclinic unit cell dimensions are a = 6.992(2), b = 19.328(4), c = 8.381(10) Å, β = 107.68(7)°, V = 1079(1)ų. This is the first reliable find of the mineral in Russia. Figures 3. Tables 3. References 24. Key words: terrywallaceite, Kochkar Au deposit, South Urals, first find of mineral in Russia, lillianite homologous series.

1,3-Bis(2,4,6-trimethylphenyl)imidazolium perchlorate

The title compound, C21H25N2 +·ClO4 −, arose as an unexpected oxidation product of the carbene 1,3-bis(2,4,6-trimethylphenyl)-1,3-dihydro-2H-imidazol-2-ylidine in methanol. It crystallizes with two unique cations and anions in the P-type monoclinic unit cell. The five-membered cationic imidazolium rings are essentially planar and in each imidazolium cation the phenyl rings of the 2,4,6-trimethylphenyl groups are staggered with respect to the imidazolium ring [dihedral angles ranging from 60.9 (3) to 86.3 (3)°]. In the crystal, a hydrogen-bonding network is created via C—H...O interactions between the imidazolium ring H atoms and the perchlorate-anion oxygen atoms. The crystal studied was refined as an inversion twin.

N,N,N-Tris(diphenylphosphorylmethyl)amine

The structure ofN,N,N-tris(diphenylphosphorylmethyl)amine, C39H36NO3P3, at 103 K has monoclinic (P21/c) symmetry. Two molecules, each with pseudo-threefold rotation symmetry, crystallize in the asymmetric unit of the monoclinic unit cell. The compound acts as ligand for the stabilization of metal ions with flexible coordination enabling three- or fourfold coordination.

A new complex alkali metal aluminium amide borohydride, Li2Al(ND2)4BH4: synthesis, thermal analysis and crystal structure

The first reported compound containing both [Al(ND2)4]− and BH4− anions, Li2Al(ND2)4BH4, was formed in ball-milled LiAl(ND2)4 + 2LiBH4 and NaAl(ND2)4 + 2LiBH4. Its crystal structure was solved and refined in a monoclinic unit cell.

Chloridobis[2-(diphenylphosphanyl)ethanamine-κ2P,N](triphenylphosphane-κP)ruthenium(II) chloride toluene monosolvate

The aminophosphane ligand 1-amino-2-(diphenylphosphanyl)ethane [Ph2P(CH2)2NH2] reacts with dichloridotris(triphenylphosphane)ruthenium(II), [RuCl2(PPh3)3], to form chloridobis[2-(diphenylphosphanyl)ethanamine-κ2P,N](triphenylphosphane-κP)ruthenium(II) chloride toluene monosolvate, [RuCl(C18H15P)(C14H16NP)2]Cl·C7H8or [RuCl(PPh3){Ph2P(CH2)2NH2}2]Cl·C7H8. The asymmetric unit of the monoclinic unit cell contains two molecules of the RuIIcation, two chloride anions and two toluene molecules. The RuIIcation is octahedrally coordinated by two chelating Ph2P(CH2)2NH2ligands, a triphenylphosphane (PPh3) ligand and a chloride ligand. The three P atoms are meridionally coordinated, with the Ph2P– groups from the ligands beingtrans. The two –NH2groups arecis, as are the chloride and PPh3ligands. This chiral stereochemistry of the [RuCl(PPh3){Ph2P(CH2)2NH2}2]+cation is unique in ruthenium–aminophosphane chemistry.

Ab initiostructure determination of bethanechol chloride

The structure of bethanechol chloride C7H17ClN2O2is solved from conventional X-ray powder diffraction data in direct space [monoclinic unit cell witha=8.8749(3) Å,b=16.4118(7) Å,c=7.1373(3) Å,β=93.803(1)°,V=1037.29(7) Å3,Z=4, and space groupP21/n]. The existence of a second orthorhombic closely related form is discussed.

Structure of a monoclinic polymorph of human carbonic anhydrase II with a doubledaaxis

The crystal structure of human carbonic anhydrase II with a doubledaaxis from that of the usually observed monoclinic unit cell has been determined and refined to 1.4 Å resolution. The diffraction data withh= 2n+ 1 were systematically weaker than those withh= 2n. Consequently, the scaling of the data, structure solution and refinement were challenging. The two molecules comprising the asymmetric unit are related by a noncrystallographic translation of ½ alonga, but one of the molecules has two alternate positions related by a rotation of approximately 2°. This rotation axis is located near the edge of the central β-sheet, causing a maximum distance disparity of 1.7 Å between equivalent atoms on the diametrically opposite side of the molecule. The crystal-packing contacts are similar to two sequential combined unit cells alongaof the previously determined monoclinic unit cell. Abnormally high finalRcrystandRfreevalues (20.2% and 23.7%, respectively) are not unusual for structures containing pseudo-translational symmetry and probably result from poor signal to noise in the weakh-odd data.

Diffraction data of Zn3Cu4Sb2O12

A new phase Zn3Cu4Sb2O12 was analyzed by X-ray powder diffraction. Its monoclinic unit cell parameters are a=21.0378(19) Å, b=8.7825(7) Å, c=5.5860(4) Å, and β=112.578(7)°, and the space group is either Cc (9) or C2/c (15). From comparison with density measurements, Z=4.

Aqua(2,2′-bipyridine-κ2 N,N′)bis(4-formylbenzoato-κ2 O,O′)cadmium(II) monohydrate

In the mononuclear title compound, [Cd(C8H5O3)2(C10H8N2)(H2O)]·H2O, the Cd atom is O,O′-chelated by two 4-formylbenzoate monoanions and N,N′-chelated by 2,2′-bipyridine. It is also coordinated by a water molecule in a monocapped trigonal-prismatic geometry. The coordinated and solvent water molecules and O atoms of the monoanions engage in hydrogen bonding, resulting in a chain running along the b axis of the monoclinic unit cell.