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Two new quaternary mixed metal oxide materials--InVTe(2)O(8) and InVSe(2)O(8)--have been synthesized, as crystals and pure bulk powders by standard solid-state reactions using In(2)O(3), V(2)O(5), and TeO(2) (or SeO(2)) as reagents. The crystal structures of the reported materials were determined using single-crystal X-ray diffraction. InVTe(2)O(8) crystallizes in the monoclinic centrosymmetric space group P2(1)/n (No. 14), with unit-cell parameters of a = 7.8967(16) Å, b = 5.1388(10) Å, c = 16.711(3) Å, β = 94.22(3)°, and Z = 4, and InVSe(2)O(8) crystallizes in the noncentrosymmetric space group Pm (No. 6) with unit-cell parameters of a = 4.6348(9) Å, b = 6.9111(14) Å, c = 10.507(2) Å, β = 97.77(3)°, and Z = 2. While the centrosymmetric InVTe(2)O(8) shows a two-dimensional (2D) layered structure composed of InO(6) octahedra, VO(4) tetrahedra, and TeO(4) polyhedra, the noncentrosymmetric InVSe(2)O(8) exhibits a three-dimensional (3D) framework structure with distorted InO(6) octahedra, VO(5) square pyramids, and SeO(3) polyhedra. Powder second-harmonic generation (SHG) measurements on InVSe(2)O(8), using 1064-nm radiation, indicate that the material has a SHG efficiency ~30 times that of α-SiO(2). Additional SHG measurements reveal that the material is not phase-matchable (Type 1). Infrared, ultraviolet-visible light (UV-vis) diffuse reflectance, and thermogravimetric analyses for the two compounds are also presented, as are dipole moment calculations.

Two new quaternary mixed-metal selenites, SrMo(2)O(5)(SeO(3))(2) and PbMo(2)O(5)(SeO(3))(2), have been synthesized as crystals and pure polycrystalline phases by standard solid-state reactions using SrMoO(4), PbO, MoO(3), and SeO(2) as reagents. The crystal structures of the reported materials have been determined by single-crystal X-ray diffraction. SrMo(2)O(5)(SeO(3))(2) and PbMo(2)O(5)(SeO(3))(2) are isostructural and crystallized in the triclinic centrosymmetric space group P1̅ (No. 2). The reported materials exhibit chain structures consisting of MoO(6) octahedra and asymmetric SeO(3) polyhedra. Complete characterizations including IR spectroscopy and thermal analyses for the compounds are also presented, as are dipole moment calculations. In addition, the powder second-harmonic-generating (SHG) properties of noncentrosymmetric polar BaMo(2)O(5)(SeO(3))(2) have been measured using 1064 nm radiation. Through powder SHG measurement, we are able to determine that BaMo(2)O(5)(SeO(3))(2) has a SHG efficiency of approximately 80 times that of α-SiO(2). Additional SHG measurements reveal that the material is phase-matchable (type 1). A detailed cation size effect on the symmetry and framework structure is discussed.

Single crystals of organically templated chiral bromobismuthates(III), [(( R / S )-C 8 H 12 N) 4 ][Bi 2 Br 10 ], have been grown for the first time via a slow evaporation method. Each of the chiral molecular compound consists of ( R ) or ( S )-1 - phenylethylammonium ([C 8 H 12 N] + ) cations and [Bi 2 Br 10 ] 4– anions. Both the title compounds reveal thermal and moisture stabilities up to ca. 220 °C and over 1 month, respectively. The newly prepared Bi 3+ -based organic–inorganic hybrid materials show optical band gap of ca. 2.88 eV. The noncentrosymmetric [(( R )-C 8 H 12 N) 4 ][Bi 2 Br 10 ] and [(( S )-C 8 H 12 N) 4 ][Bi 2 Br 10 ] exhibit second harmonic generation efficiency of ca. 20 times that of α-SiO 2 and are type I nonphase matchable. Uniformly deposited thin films of [(( R )-C 8 H 12 N) 4 ][Bi 2 Br 10 ] and [(( S )-C 8 H 12 N) 4 ][Bi 2 Br 10 ] have been also successfully obtained by a simple spin-coating method. The circular dichroism spectra for both reported thin films are symmetrical, attributable to the corresponding Cotton effect. The selectively deposited chiral thin films are expected to be used as a useful platform for various surface reactions and interface engineering.

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Two new isostructural mixed metal selenites, PbMSeO(6) (M = Mo(6+) or W(6+)), that are only composed of second-order Jahn-Teller (SOJT) distortive cations have been synthesized by standard solid-state reaction techniques using PbO, SeO(2), and MoO(3) (or WO(3)) as reagents. The structures of the reported materials were determined by single-crystal and powder X-ray diffraction. The materials show a three-dimensional framework structure consisting of chains of corner-shared MO(6) octahedra connected by SeO(3) and PbO(8) polyhedra. All of the constituent cations (M(6+), Se(4+), and Pb(2+)) are in distorted environments attributable to second-order Jahn-Teller (SOJT) effects. While the Mo(6+) cations undergo a C(2)-type intraoctahedral distortion toward an edge, the Se(4+) and Pb(2+) cations are in asymmetric coordination environments attributable to their lone pairs. The SeO(3) polyhedra strongly influence the direction of the Mo(6+) intraoctahedral distortion. Infrared spectroscopy, thermogravimetric analysis, the magnitudes of out-of-center distortions, and dipole moment calculations are also presented. Crystal data: PbMoSeO(6), triclinic, space group P-1 (No. 2), with a = 6.8944(6) Å, b = 7.2219(6) Å, c = 10.8294(9) Å, α = 99.751(2)°, β = 99.996(2)°, γ = 90.041(2)°, V = 523.09(8) Å(3), and Z = 2; PbWSeO(6), triclinic, space group P-1 (No. 2), with a = 6.8689(2) Å, b = 7.2398(2) Å, c = 10.9037(3) Å, α = 99.699(4)°, β = 100.348(3)°, γ = 90.139(4)°, V = 525.50(3) Å(3), and Z = 2.

Although liver function test abnormality is frequently noted in children, there is no report about the distribution of the etiology and natural recovery time of the abnormal liver function. From March 2005 to February 2014, clinical information was retrospectively collected from 559 children who had abnormal liver function and were hospitalized or visited the outpatient clinic at the Jeju National University Hospital. The etiology of abnormal liver function was classified into groups and the natural recovery time of abnormal liver function was analyzed. The etiological groups of 559 patients included ‘nonspecific hepatitis’ in 42 (7.5%), ‘infection’ in 323 (57.8%), ‘rheumatologic and autoimmune’ in 66 (11.8%), ‘nonalcoholic fatty liver disease’ in 57 (10.2%), ‘anatomic’ in 12 (2.1%), ‘toxic’ in 13 (2.1%), ‘metabolic’ in 8 (1.4%), ‘hematologic’ in 7 (1.3%), ‘hemodynamic’ in 4 (0.7%), and ‘others’ in 27 (4.8%). Among the ‘infection’ group (57.8%), the ‘viral infection in the respiratory tract’ subgroup, which had 111 patients (19.8%), was the most common. The natural recovery time of the abnormal liver function was 27 days (median) in ‘nonspecific hepatitis’, 13 days (median) in ‘viral respiratory tract disease’, 16 days (median) in ‘viral gastroenteritis’, 42 days (median) in ‘viral febrile illness”, and 7 days (median) in “Kawasaki disease”. The information on the natural recovery time of abnormal liver function may help the physician to perform good clinical consultation for patients and their parents.