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An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Here, we report the detail synthesis, single crystal structure characterization and magnetic properties of KLnSe 2 series obtained via solid state molten flux growth method. The crystal structures were characterized using single crystal x-ray diffraction. The KLnSe 2 (Ln = La, Ce, Pr and Nd) series crystallizes in the trigonal crystal system with the space group of R-3m (No. 166). The overall structure contains two-dimensional (2D) layers made from edged shared LnSe 6 -octahedra. Ln 3+ ions form a perfect triangular magnetic lattice which propagates along ab-plane. These triangular lattices are separated by the K + ions. The magnetic properties confirm that, Ce, Pr and Nd do not show any long-range ordering down to 0.4 K indicating frustrated magnetism in the KLnSe 2 series.
The crystal structure of perfluorononanoic acid (PFNA) was solved via parallel tempering using synchrotron powder diffraction data obtained from the Brockhouse X-ray Diffraction and Scattering (BXDS) Wiggler Lower Energy (WLE) beamline at the Canadian Light Source. PFNA crystallizes in monoclinic space group P2 1 /c (#14) with lattice parameters a = 26.172(1) Å, b = 5.6345(2) Å, c = 10.9501(4) Å, and β = 98.752(2)°. The crystal structure is composed of dimers, with pairs of PFNA molecules connected by hydrogen bonds via the carboxylic acid functional groups. The Rietveld-refined structure was compared to a density functional theory-optimized structure, and the root-mean-square Cartesian difference was larger than normally observed for correct powder structures. The powder data likely exhibited evidence of disorder which was not successfully modeled.
Phase-pure polycrystalline Ba 4 RuMn 2 O 10 was prepared and determined to adopt the noncentrosymmetric polar crystal structure (space group Cmc2 1 ) based on results of second harmonic generation, convergent beam electron diffraction, and Rietveld refinements using powder neutron diffraction data. The crystal structure features zigzag chains of corner-shared trimers, which contain three distorted face-sharing octahedra. The three metal sites in the trimers are occupied by disordered Ru/Mn with three different ratios: Ru1:Mn1 = 0.202(8):0.798(8), Ru2:Mn2 = 0.27(1):0.73(1), and Ru3:Mn3 = 0.40(1):0.60(1), successfully lowering the symmetry and inducing the polar crystal structure from the centrosymmetric parent compounds Ba 4 T 3 O 10 (T = Mn, Ru; space group Cmca). The valence state of Ru/Mn is confirmed to be +4 according to X-ray absorption near-edge spectroscopy. Ba 4 RuMn 2 O 10 is a narrow bandgap (~0.6 eV) semiconductor exhibiting spin-glass behavior with strong magnetic frustration and antiferromagnetic interactions.
Unconditional crystal structure generation with diffusion models faces challenges in identifying symmetric crystals as the unit cell size increases. Here, we present the crystal host-guided generation (CHGGen) framework to address this challenge through conditional generation using an inpainting method, which optimizes a fraction of atomic positions within a predefined and symmetrized host structure to improve the success rate for symmetric structure generation. By integrating inpainting structure generation with a foundation potential for structure optimization, we demonstrate the method on the ZnS–P 2 S 5 and Li–Si chemical systems, where the inpainting method generates a higher fraction of symmetric structures than unconditional generation. The practical significance of CHGGen extends to enabling the structural modification of crystal structures, particularly for systems with partial occupancy or intercalation chemistry. The inpainting method also allows for seamless integration with other generative models, providing a versatile framework for accelerating materials discovery.
The crystal structure of toceranib has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Toceranib crystallizes in space group P2 1 /c (#14) with a = 10.6899(6), b = 24.5134(4), c = 7.8747(4) Å, β = 107.7737(13)°, V = 1965.04(3) Å 3 , and Z = 4. The crystal structure consists of stacks of approximately planar molecules, with N–H∙∙∙O hydrogen bonds between the layers. The commercial reagent sample was a mixture of two or more phases with toceranib being the dominant phase. The difference between the Rietveld-refined and DFT-optimized structures is larger than usual. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®).
The crystal structure of oxfendazole has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Oxfendazole crystallizes in space group P2 1 /c (#14) with a = 18.87326(26), b = 10.40333(5), c = 7.25089(5) Å, β = 91.4688(10)° V = 1423.206(10) Å 3 , and Z = 4. The crystal structure consists of stacks of the planar portions of the L-shaped molecules, resulting in layers parallel to the bc-plane. Only weak hydrogen bonds are present. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®).
The crystal structure of valbenazine has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Valbenazine crystallizes in space groupP2 1 2 1 2 1 (#19) witha= 5.260267(17),b= 17.77028(7),c= 26.16427(9) Å,V= 2445.742(11) Å 3 , andZ= 4 at 295 K. The crystal structure consists of discrete molecules and the mean plane of the molecules is approximately (8,−2,15). There are no obvious strong intermolecular interactions. There is only one weak classical hydrogen bond in the structure, from the amino group to the ether oxygen atom. Two intramolecular and one intermolecular C–H⋯O hydrogen bonds also contribute to the lattice energy. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®)
The crystal structure of ractopamine hydrochloride has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Ractopamine hydrochloride crystallizes in space groupPbca(#61) witha= 38.5871(49),b= 10.7691(3),c= 8.4003(2) Å,V= 3490.75(41) Å 3 , andZ= 8. The ractopamine cation contains two chiral centers, and the sample consists of a mixture of the S,S/R,R/S,R and R,S forms. Models for the two diastereomers S,S and S,R were refined, and yielded equivalent residuals, but the S,R form is significantly lower in energy. The crystal structure consists of layers of molecules parallel to thebc-plane. In each structure one of the H atoms on the protonated N atom acts as a donor in a strong discrete N–H⋯Cl hydrogen bond. Hydroxyl groups act as donors in O–H⋯Cl and O–H⋯O hydrogen bonds. Both the classical and C–H⋯Cl and C–H⋯O hydrogen bonds differ between the forms, helping to explain the large microstrain observed for the sample. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).
The crystal structure of elvitegravir Form II has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Elvitegravir Form II crystallizes in space group P2 1 (#4) with a = 11.54842(7), b = 14.04367(5), c = 13.33333(8) Å, β = 90.0330(6)°, V = 2162.427(14) Å 3 , and Z = 4. The crystal structure consists of alternating layers of parallel molecules perpendicular to the b-axis. The mean planes of the oxoquinoline ring systems in molecules 1 and 2 are 1(22)-1 and -1(22)1. Between the stacks are layers of the halogenated phenyl rings. These exhibit herringbone stacking. In each molecule, the carboxylic acid group forms a strong intramolecular O–H∙∙∙O hydrogen bond to the nearby carbonyl group. The hydroxyl group of each molecule forms a strong hydrogen bond to the carbonyl group of the carboxylic acid of the other molecule. These O–H∙∙∙O hydrogen bonds link the molecules into dimers, with a graph set R2,2(18) > a > c. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®).
The crystal structure of danofloxacin mesylate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Danofloxacin mesylate crystallizes in space group P1 (#1) with a = 6.77474(8), b = 12.4973(4), c = 12.82826(28) Å, α = 84.8709(29), β = 87.7501(10), γ = 74.9916(4)°, V = 1044.723(11) Å 3 , and Z = 2. The protonation of the danofloxacin cations was established by the analysis of potential intermolecular interactions and differs from that expected from isolated-cation calculations. The crystal structure consists of alternating layers of cations and anions parallel to the ac-plane. There is parallel stacking of the oxoquinoline rings along the a-axis. The expected N–H∙∙∙O hydrogen bonds between the cations and anions are not present. Each cation makes an N–H∙∙∙O hydrogen bond with the other cation, resulting in zig-zag chains along the a-axis. Both cations have strong intramolecular O–H∙∙∙O hydrogen bonds. There are several C–H∙∙∙O hydrogen bonds between the danofloxacin cations and mesylate anions. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).
We report the first crystal structure of a Pu(VI)-oxalate compound. This compound, [PuO 2 (C 2 O 4 )(H 2 O)]·2(H 2 O) (1), crystallizes in space group P21/c with a = 5.5993(3) Å, b = 16.8797(12) Å, c = 9.3886(6) Å, and β = 98.713(6)°. It is isostructural with the previously reported U(VI) compound, [UO 2 (C 2 O 4 )(H 2 O)]·2(H 2 O). Each plutonyl ion (PuO 2 2+ ) is coordinated in the equatorial plane by two side-on bidentate oxalates, creating an infinite chain along [001]. A coordinated water molecule and twisting of the oxalates lead to a distorted pentagonal bipyramidal geometry of the Pu. A photochemical degradation was observed for 1, which resulted in the formation of a secondary crystalline phase. The absorption spectrum of this secondary phase confirmed the presence of Pu(IV), but it did not match the spectrum of Pu(C 2 O 4 ) 2 ·6H 2 O, which is considered to be the primary product of Pu-oxalate precipitation. While compound 1 has previously been proposed to exist in solution, this is the first time it has been isolated via crystallization. Although redox interactions between Pu and oxalate have been documented in the literature, the present study is the first observation of a photochemical reduction of Pu(VI)-oxalate. Finally, this study has expanded on the limited understanding of the Pu(VI)-oxalate system, which is important for nuclear fuel cycle applications.