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A mononuclear low spin ( S = 1/2) Co(II) molecule crystallized in a 4-fold symmetry is fully investigated by CW and pulsed EPR on a single crystal sample. The quantum phase memory time of the molecule around 1 μs at 5 K is direction-independent, while the Rabi oscillation frequency is anisotropic. The spin Hamiltonian analyses reveal that the anisotropic Landé factor and hyperfine tensor do not influence the anisotropy apparently when the microwave magnetic field is applied along a certain direction. It is considered that the possibly involved nuclear spin forbidden transitions may be responsible for the small distinction of Rabi frequencies in two directions.

Two-dimensional zeolitic materials have drawn increasing attention because of their structural diversity, high accessible surface areas, and potential as precursors to form novel three-dimensional (3D) structures. Here we report a new layered fluoroaluminophosphate, denoted as EMM-9 (ExxonMobil Material #9), synthesized in the same synthesis system as that for a previously reported 3D framework structure EMM-8 (framework-type code: SFO) using an F– medium and 4-(dimethylamino)pyridine (DMAP) as the organic structure-directing agent. The structure of EMM-9 was solved from rotation electron diffraction data and refined against synchrotron powder X-ray diffraction data. The fluoroaluminophosphate layer of EMM-9 is composed of sti composite building units. The DMAP cations are located between the layers. π–π interactions between the DMAP cations and hydrogen bonding between the DMAP cations and layers were identified. The layered EMM-9 structure is closely related to the 3D framework structure of EMM-8 and ca...

The aluminosilicate zeolite ZSM-43 (where ZSM = Zeolite Socony Mobil) was first synthesized more than 3 decades ago, but its chemical structure remained unsolved because of its poor crystallinity and small crystal size. Here we present optimization of the ZSM-43 synthesis using a high-throughput approach and subsequent structure determination by the combination of electron crystallographic methods and powder X-ray diffraction. The synthesis required the use of a combination of both inorganic (Cs+ and K+) and organic (choline) structure-directing agents. High-throughput synthesis enabled a screening of the synthesis conditions, which made it possible to optimize the synthesis, despite its complexity, in order to obtain a material with significantly improved crystallinity. When both rotation electron diffraction and high-resolution transmission electron microscopy imaging techniques are applied, the structure of ZSM-43 could be determined. The structure of ZSM-43 is a new zeolite framework type and possesse...

Polycrystalline and monocrystalline alpha-BiFeO3 crystals have been synthesized by solid state reaction and flux growth method, respectively. X-ray, neutron, and electron diffraction techniques are used to study the crystallographic and magnetic structure of alpha-BiFeO3. The present data show that alpha-BiFeO3 crystallizes in space group PI with a = 0.563 17(1) nm, b = 0.563 84(1) nm, c = 0.563 70(1) nm, alpha = 59.33(1)degrees, beta = 59.35(1)degrees, gamma = 59.38(1)degrees, and the magnetic structure of alpha-BiFeO3 can be described by space group PI with magnetic modulation vector in reciprocal space q = 0.0045a* - 0.0045b*, which is the magnetic structure model proposed by I. Sosnowska(1) applied to the new PI crystal symmetry of alpha-BiFeO3

In this study, we report the formation of a new crystal structure, ZIF-CO3-1, which results from the reaction of Zn(2+), 2-methylimidazole, and carbonate. ZIF-CO3-1 can be synthesized solvothermally in N,N-dimethylformamide (DMF)/water (H2O) or by utilizing of CO2 gas at various temperatures in DMF/H2O or H2O. This reaction selectively consumes CO2 because CO2 is incorporated in the ZIF as carbonate. CO2 can be quantitatively released by acidifying the ZIF. Powder X-ray diffraction, single-crystal X-ray diffraction, FTIR spectroscopy, scanning electron microscopy, elemental analysis, and thermogravimetric analysis were used to characterize the ZIF structure. ZIF-CO3-1 (chemical formula C9H10N4O3Zn2), crystallizes in the orthorhombic crystal system with noncentrosymmetric space group Pba2.

Three new indium(III) compounds, In(HCOO)3 (1), In2(HCOO)5(OH) (2), and In(HCOO)2(OH) (3), were synthesized under hydrothermal conditions and characterized by single crystal and powder X-ray diffraction experiments, as well as by IR spectroscopy, elemental analysis, and coupled TG-DSC-MS measurement. All of these compounds adopt 3D framework structures consisting of InO6 octahedra and the 2.11 binding modes of formate with the (syn, syn-; syn, anti-; anti, anti-) configurations. The structural investigation of these indium formates reveals that the gradual introduction of the hydroxyl groups into the structures induces the polymerization of the InO6 octahedra, that is, InO6 is isolated in 1, becomes dimeric in 2, and finally forms 1D chains in 3. In addition, a simple formula that may be used for estimating the overall coordination number of the formate in Ma(HCOO)bLc is proposed.