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The title complex, trans-bis(dimethylformamide-κ O)bis{ N, N′- N′′, N′′′-tetra- tert-butyl[oxybis(phosphonic diamide-κ O)]}manganese(II) dichloride dihydrate, [Mn(C16H40N4O3P2)2(C3H7NO)2]Cl2·2H2O, is the first example of a bis-chelate amido-pyrophosphate (pyrophosphoramide) complex containing an O[P(O)(NH)2]2 fragment. Its asymmetric unit contains half of the complex dication, one chloride anion and one water molecule. The MnII atom, located on an inversion centre, is octahedrally coordinated, with a slight elongation towards the monodentate dimethylformamide ligand. Structural features of the title complex, such as the P=O bond lengths and the planarity of the chelate ring, are compared with those of previously reported complexes with six-membered chelates involving the fragments C(O)NHP(O), ( X)NP(O) [ X = C(O), C(S), S(O)2 and P(O)] and O[P(O)(N)2]2. This analysis shows that the six-membered chelate rings are less puckered in pyrophosphoramide complexes containing a P(O)OP(O) skeleton, such as the title compound. The extended structure of the title complex involves a linear aggregate mediated by N-H...O and N-H...Cl hydrogen bonds, in which the chloride anion is an acceptor in two additional O-H...Cl hydrogen bonds. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structure of kasolite, Pb[(UO2)(SiO4)](H2O), Z =4, monoclinic, with a =6.7050(3), b =6.9257(2), c =13.2857(5)Å, β =105.064(4)°, V =595.74(3)Å3, the space group P21/c, has been solved by charge-flipping method and refined by the full-matrix least-squares techniques to an agreement factor (R obs) of 2.2% and, a goodness-of-fit (GOF) of 1.26 using 1243 unique observed diffraction maxima (I obs >3σ(I)) collected with MoKα X-radiation and a 4K CCD area detector. The crystal structure of kasolite contains 1 unique U6+ position that is part of a nearly linear uranyl ion (UO2)2+, coordinated in the equatorial plane by five O ligands, forming pentagonal bipyramid. The uranyl pentagonal bipyramids share edges to form chains parallel to [010]. The additional edge of uranyl polyhedra is shared by silicate tetrahedra to form sheets parallel to (100). There is one unique position of Pb2+ in the interlayer. O ligands and 1 (H2O) non-transformer group coordinate Pb2+ exhibiting [2+6] coordination. A network of H-bonds provides an additional linkage of an interlayer to the sheets besides Pb–O bonds. Chemical composition of the studied crystals, obtained by the electron microprobe, is reported and is in agreement with the crystal structure refinement. [Copyright &y& Elsevier]

In N, N′-di- tert-butyl- N′′, N′′-dimethylphosphoric triamide, C10H26N3OP, (I), and N, N′, N′′, N′′′-tetra- tert-butoxybis(phosphonic diamide), C16H40N4O3P2, (II), the extended structures are mediated by P(O)...(H-N)2 interactions. The asymmetric unit of (I) consists of six independent molecules which aggregate through P(O)...(H-N)2 hydrogen bonds, giving R21(6) loops and forming two independent chains parallel to the a axis. Of the 12 independent tert-butyl groups, five are disordered over two different positions with occupancies ranging from to . In the structure of (II), the asymmetric unit contains one molecule. P(O)...(H-N)2 hydrogen bonds give S(6) and R22(8) rings, and the molecules form extended chains parallel to the c axis. The structures of (I) and (II), along with similar structures having (N)P(O)(NH)2 and (NH)2P(O)(O)P(O)(NH)2 skeletons extracted from the Cambridge Structural Database, are used to compare hydrogen-bond patterns in these families of phosphoramidates. The strengths of P(O)[...H-N] x ( x = 1, 2 or 3) hydrogen bonds are also analysed, using these compounds and previously reported structures with (N)2P(O)(NH) and P(O)(NH)3 fragments. [ABSTRACT FROM AUTHOR]

Two polymorphs of bis(2-carbamoylguanidinium) fluorophosphonate dihydrate, 2C2H7N4O+·FO3P2−·2H2O, are presented. Polymorph (I), crystallizing in the space group Pnma, is slightly less densely packed than polymorph (II), which crystallizes in Pbca. In (I), the fluorophosphonate anion is situated on a crystallographic mirror plane and the O atom of the water molecule is disordered over two positions, in contrast with its H atoms. The hydrogen-bond patterns in both polymorphs share similar features. There are O-H...O and N-H...O hydrogen bonds in both structures. The water molecules donate their H atoms to the O atoms of the fluorophosphonates exclusively. The water molecules and the fluorophosphonates participate in the formation of R44(10) graph-set motifs. These motifs extend along the a axis in each structure. The water molecules are also acceptors of either one [in (I) and (II)] or two [in (II)] N-H...O hydrogen bonds. The water molecules are significant building elements in the formation of a three-dimensional hydrogen-bond network in both structures. Despite these similarities, there are substantial differences between the hydrogen-bond networks of (I) and (II). The N-H...O and O-H...O hydrogen bonds in (I) are stronger and weaker, respectively, than those in (II). Moreover, in (I), the shortest N-H...O hydrogen bonds are shorter than the shortest O-H...O hydrogen bonds, which is an unusual feature. The properties of the hydrogen-bond network in (II) can be related to an unusually long P-O bond length for an unhydrogenated fluorophosphonate anion that is present in this structure. In both structures, the N-H...F interactions are far weaker than the N-H...O hydrogen bonds. It follows from the structure analysis that (II) seems to be thermodynamically more stable than (I). [ABSTRACT FROM AUTHOR]

The title compounds, 2-carbamoylguanidinium hydrogen fluorophosphonate, C2H7N4O+·HFO3P−, (I), 2-carbamoylguanidinium-hydrogen fluorophosphonate-hydrogen phosphite (1/0.76/0.24), C2H7N4O+·0.76HFO3P−·0.24H2O3P−, (II), and 2-carbamoylguanidinium-hydrogen fluorophosphonate-hydrogen phosphite (1/0.115/0.885), C2H7N4O+·0.115HFO3P−·0.885H2O3P−, (III), are isostructural with guanylurea hydrogen phosphite, C2H7N4O+·H2O3P− [Fridrichová, Němec, Císařová & Němec (2010). CrystEngComm, 12, 2054-2056]. They constitute structures where the hydrogen phosphite anion has been fully or partially replaced by hydrogen fluorophosphonate. The title structures are the fourth example of isostructural compounds which differ by the presence of hydrogen fluorophosphonate and hydrogen phosphite or fluorophosphonate and phosphite anions. Moreover, the present study reports structures with these mixed anions for the first time. In the reported mixed salts, the P and O atoms of either anion overlap almost exactly, as can be judged by comparison of their equivalent isotropic displacement parameters, while the P-F and P-H directions are almost parallel. There are strong O-H...O hydrogen bonds between the anions, as well as strong N-H...O hydrogen bonds between the 2-carbamoylguanidinium cations in the title structures. Altogether they form a three-dimensional hydrogen-bond pattern. Interestingly, rare N-H...F interactions are also present in the title structures. Another exceptional feature concerns the P-O(H) distances, which are about as long as the P-F distance. The dependence of P-F distances on the longest P-O distances in FO3P2− or HFO3P− is presented. The greater content of hydrogen phosphite in the mixed crystals causes a larger deformation of the cations from planarity. [ABSTRACT FROM AUTHOR]

The title compound, C7H12N4O2, was obtained by nitrosation of the aminal cage (2 R,7 R,11 S,16 S)-1,8,10,17-tetraazapentacyclo[8.8.1.18,17.02,7.011,16]icosane. The crystal structure is a racemic mixture of RR and SS enantiomers. The asymmetric unit contains two crystallographically independent half-molecules, one having two partially occupied conformers with refined occupancy factors of 0.747 (3) and 0.253 (3). The molecules sit across twofold axes. The unique molecules each form chains parallel to [001], with molecules connected by intermolecular C-H...O hydrogen bonds. The bonding between adjacent chains is weak. The analysis of eight different crystals confirmed the presence of disordered and nondisordered molecules in the same structure as a regular feature. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the crystal structure contains one molecule of the title compound and one molecule of water. X-ray diffraction spectrum of the ammonium salt of title compound exhibits deviations from the ideal molecular geometry which is explained on the basis of anomeric effect. This conclusion is consistent with the natural bond orbital analysis at the B3LYP/6-311+G** level of the anomeric effect. The molecules are linked via N-H···O hydrogen bonds. This compound crystallizes in monoclinic symmetry, in space group P2, with lattice constants: a = 12.3850(2) Å, b = 6.8123(1) Å, c = 19.6208(4) Å, α = 90°, β = 94.864(2)°, γ = 90°, V = 1649.45(5) Å, Z = 4, F(000) = 896, R = 3.3%, wR = 10.6%. Graphical Abstract: [Figure not available: see fulltext.]. [ABSTRACT FROM AUTHOR]

A phase transition was found to occur at ∼153 K in the title compound, (C8H20N)2[PdC16]. The structures of the two phases are reported at 292 and 130 K. The low-temperature phase is twinned. The phase transition is accompanied by a minor displacement of the ions. There are C—H…C1 interactions as short as ∼2.80 Å, indicating the existence of hydrogen bonds, and this was confirmed by vibrational spectroscopy. The [Pd2C16]2- anion occupies sites of mmm and 2/m symmetry in the room-temperature and low-temperature phases, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Hirshfeld surfaces and two-dimensional fingerprint plots are used to study short intermolecular contacts in new organotin(IV)-phosphoramide complexes, (L 1 )2Cl2Me2Sn (1), (L 2 )Cl2Me2Sn (2) and (L 3 )2Cl2Me2Sn (3) [L 1 = (C5H9NH)3PO, L 2 = [(CH3)3CNH][C6H5CH2N(CH3)]2PO and L 3 = (3-F-C6H4C(O)NH)(N(CH3)C6H11)2PO]. The previously reported structure L 3 is also analyzed for a comparison with the related complex, 3. While 2 and 3, respectively, contain one independent molecule and one-half of a molecule, the asymmetric unit of 1 is composed of three independent molecules with different conformations of ligands around the tin center but with very similar Hirshfeld surfaces and fingerprint plots. The SnIV coordination geometries are octahedral for 1 and 3 with cis-phosphoramides in each independent molecule of 1 and trans-phosphoramides in 3. For 2, the SnIV adopts a distorted trigonal bipyramidal environment with the axial positions occupied by the ligand phosphoramide and one Cl atom. Two-dimensional fingerprint plots of 1 and 2 show pairs of spikes attributed to the intermolecular H⋯Cl contacts including N–H⋯Cl hydrogen bonds. Two spikes found in 3 are much shorter comparing with 1 and 2 due to absence of the intermolecular N–H⋯Cl hydrogen bond and lower contribution of C–H⋯Cl contacts. In the ligand L 3 the presence of N–H⋯O P hydrogen bond is reflected as a deep-red area of Hirshfeld surfaces. Moreover, in fingerprint plot of L 3 two intense spikes are observed related to the intermolecular H⋯O contacts including N–H⋯O P hydrogen bond. The more shallow red spots on the Hirshfeld surface of 3 with respect to L 3 are caused by absence of N–H⋯O hydrogen bond and the lower contribution of H⋯O contacts. [Copyright &y& Elsevier]