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The polar compound Pb2(SeO3)(NO3)2 is prepared by hydrothermal reaction of Pb(NO3)2, SeO2, and H2O (autoclave, 200 °C, 4 d, 75% yield).

Pale brown crystals of Ba2Sb7O13(OH) are prepared by hydrothermal reaction of Ba(OH)2, Sb2O3, KCl, and H2O (autoclave, 190 °C, 4 d).

PbGa2SiSe6 (I) and PbGa2GeSe6 (II) with mid-IR second-order nonlinear optical responses are prepared by solid-state reaction of PbSe, Ga2Se3, Si (Ge), and Se in the molar ratio 1:1:1:2 (evacuated silica tube, 1023 K (1073 K for (II)), 50 h; cooling to 573 K with a rate of 3 K/h).

Crystals of [LaPb8O(OH)10(H2O)] (NO3)7 (I) and [LaPb8O(OH)10(H2O)] (NO3)7·2H2O (II) are hydrothermally synthesized under subcritical conditions from mixtures of Pb(NO3)2, H2O, and 0.5 and 1 equiv.

Single crystals of the title compound are prepared by solid state reaction of Na2CO3, Mn(OAc)2, NH4H2PO4, and KF (alumina crucible, 1153 K, 40 h).

Compounds (IV) and (VII) are characterized by single crystal XRD, UV/VIS diffuse reflectance spectroscopy, second harmonic generation measurements, and DFT electronic structure calculations.

Pb(II) oxide hydroxide nitrates are prepared under subcritical hydrothermal conditions by adjusting the pH values of the Pb(NO3)2—NaOH reaction system.

The new title compound is synthesized by solid state reaction of Sn, BaS, and sulfur (graphite crucible, 1073 K, 48 h

The two new title compounds (IV) and (V) are characterized by single crystal XRD, UV/VIS diffuse reflectance spectroscopy, second harmonic generation measurements, and DFT computations.

The title compound is hydrothermally synthesized from an aqueous mixture of Sb2O3, Sr(OH)2, and KF as mineralizer (autoclave, 190 °C, 4 d, 45% yield).

The title compound is synthesized by solid state reaction of BaF2, Mn, and Se in closed silica tubes at 1253 K for 72 h.

The title compound is synthesized by solid state reaction of SrCl2, CoC2O4, H3BO3, and (NH4)H2PO4 (alumina crucible, 1050 °C, 3 d).

Single crystals of the new title compounds are prepared by solid state reaction of stoichiometric mixtures of BaS, Sn, and S (graphite crucible in an evacuated silica tube, 973—1073 K, 30 h).

The title compounds are quantitatively prepared by solid state reaction of Bi2O3, Co(OAc)2 or Ni(HCO2)2, H3BO3, and NH4H2PO4 in a molar ratio of 1:4:2:4 (1123 or 1193 K, 30 h).

Single crystals of the title compound are synthesized by solid state reaction of K2CO3, Fe2O3, NH4H2PO4, and KF (alumina crucible, 1050 °C, 10 h).

The title compounds are prepared by solid state reactions of stoichiometric mixtures of BaS, Bi, Ga or In, and sulfur (silica tubes, 973 K and 1223 K, 30 h each).

Magnetic measurements on single crystals of the title compound show that it exhibits an unexpected large magnetic anisotropy energy of up to 107 erg/cm3 at 5 K.

Single crystals of the new title compounds are synthesized by solid state reactions of BaS, Sb or Bi, Fe, and S (silica tubes, 1123 K, 30 h).

The title compounds are prepared by solid state reactions of BaS, Bi (or Sb), B, and S in the molar ratios of 1:1:1:3 (graphite crucibles, 1100 K, 10 h) and characterized by single crystal XRD, UV/VIS spectroscopy, and DFT electronic structure calculations.

The title compounds are obtained quantitatively by reacting mixtures of M2O3 (M: Fe, In), H3BO3, and NH4H2PO4 in a molar ratio of 1:1:3 at 1153 K.

Explorations of the AI−MIII−BIII−PV−O quinary system under solid-state reactions led to an anhydrous cesium−chromium borophosphate−phosphate and an anhydrous cesium−iron borophosphate, namely, Cs2C...

The title compound was synthesized by high-temperature solution reaction and its structure determined by X-ray diffraction techniques. The structure contains Ca 4 O 19 tetramers which form double chains extending along the a direction. The double chains are linked to form layers and B 2 O 5 groups bridge these adjacent chains and adjacent layers through O atoms to form a three-dimensional framework.

In this communication, the novel nonlinear optical crystal material Cd4BiO(BO3)3 with 3-chromophore asymmetric structures of CdOn, BiO6, and BO3 groups has been prepared by a flux method, and the s...

Two compounds Pb2In4P6O23 and Pb2InP3O11 in the new family of lead indium phosphates were synthesized by high temperature solution growth (HTSG) method and structurally characterized by X-ray single crystal diffraction, powder diffraction and electron microscopy. Two title compounds display different types of 3D architectures with interesting tunnel structure are built up of the InO6 octahedra and PO4 tetrahedra, sharing the corners or edges, and the Pb2+ cations are sitting in the tunnel. The structure of Pb2In4P6O23 features a novel 3D open framework which can be considered as built from the layer of {In4(P2O7)(PO4)2}2− parallel to the ac plane interconnected by bridging the single PO4. The structure of Pb2InP3O11 can be described by the assemblage of [InP2O11] units with monophosphate groups. The stereochemical activity of the PbII lone pair has also been discussed. The electronic band structure calculations for the two compounds have also been performed with the density functional theory method. The study of calculations and optical diffuse reflectance absorption spectrum measurement show both compounds are indirect band-gap insulators.

Based on the phase diagram of CoO–V2O5 system, single crystals of Co2V2O7 are grown using V2O5 as self-flux at a slow cooling rate. The quality of grown crystals is analyzed by X-ray powder diffraction and electron probe microanalysis techniques. Magnetic properties are investigated by means of susceptibility, magnetization, and heat capacity measurements. Our experimental results suggest that Co2V2O7 is a three-dimensional antiferromagnet, in which two magnetic transitions may occur at low temperature and a spin-flop-like transition may occur at the applied field along the b-axis. By contrast to Ni2V2O7, it is suggested that similar and different magnetic properties may arise from their similar crystal structures and different magnetic ions, respectively.

Two new isotypic anhydrous borophosphates, KMBP(2)O(8) (M = Sr, Ba), have been prepared under high temperature solution growth (HTSG). Investigation of single-crystal X-ray diffraction shows that they crystallize in noncentrosymmetric space group I42d with the following lattice parameters: a = 7.1095(18), c = 13.882(5)A for KSrBP(2)O(8) and a = 7.202(2), c = 14.300(6)A for KBaBP(2)O(8). The fundamental building block (FBB) of title borophosphates with B:P ratio = 1:2 is 12square: (symbol square represents BO(4) and PO(4) tetrahedra). The FBBs are further interlocked together to form the final 3D diamond-like architecture. Second-harmonic generation (SHG) on powder samples has been measured using Kurtz and Perry technique, which indicates that they are phase-matchable materials, and their SHG coefficients are measured to be about 1/5 (for KSrBP(2)O(8)) and 1/3 (for KBaBP(2)O(8)) times as large as that of KDP.

A sodium gadolinium phosphate crystal, Na 3 GdP 2 O 8 , has been synthesized by a high-temperature solution reaction, and it exhibits a new structural family of the alkali-metal-rare-earth phosphate system. Although many compounds with formula M 3 LnP 2 O 8 have been reported, but they were shown to be orthorhombic [R. Salmon, C. Parent, M. Vlasse, G. LeFlem, Mater. Res. Bull. 13 (1978) 439] rather than monoclinic as shown in this paper. Single-crystal X-ray diffraction analysis shows the structure to be monoclinic with space group C 2/ c and the cell parameters: a =27.55 (25), b =5.312 (4), c =13.935(11) A, β =91.30(1)°, and V =2038.80 A 3 , Z =4. Its structure features a three-dimensional GdP 2 O 8 3− anionic framework with two different types of interesting tunnels at where Na atoms are located by different manners. The framework is constructed by Gd polyhedra and isolated PO 4 tetrahedra. It is different from the structure of K 3 NdP 2 O 8 [R. Salmon, C. Parent, M. Vlasse, G. LeFlem, Mater. Res. Bull. 13 (1978) 439] with space group P 2 1 / m that shows only one type of tunnel. The emission spectrum and the absorption spectrum of the compound have been investigated. Additionally, the calculations of band structure, density of states, dielectric constants, and refractive indexes have been also performed with the density functional theory method. The obtained results tend to support the experimental data.

Sodium rare earth diphosphates NaLnP2O7 (Ln = Ce (1), Eu (2)) and polyphosphates NaLn(PO3)4 (Ln = Ce (3), Eu (4)) have been synthesized by the high temperature solution reaction. These compounds have been characterized by means of single-crystal X-ray diffraction, elemental analyses, spectral measurements, and theoretical computations. Their structural characteristics are described, and the differences among them are compared. The nature of chemical bonds and electronic origins of optical transitions are analyzed for 1 and 3 in terms of crystal band structures, density of states (DOS), and optical response functions which have been calculated by the DFT method. Results of spectral measurements indicate that crystals 1 and 3 may become promising hosts for ultraviolet-emitting solid-state light sources, and crystals 2 and 4 exhibit the characteristic yellow–red light emission under the excitation of ultraviolet light.

Solid-state reactions of zinc(II) or cadmium(II) oxide,V 2O5, and TeO2 at high temperature led to two novel quaternary compounds, namely,Zn 3V2TeO 10 and Cd4V2Te 3O15. The structure of Zn3V2TeO 10 is a com- plicated three-dimensional (3D) net- work constructed by the interconnec- tion of ZnO5,ZnO 6,VO 4,and TeO 4 polyhedra via corner- and edge-sharing. Cd4V2Te 3O15 with an acentric structure features a 3D network in which the cadmium tellurite layers are further in- terconnected by both "isolated" VO4 tetrahedra and one-dimensional (1D) vanadium oxide helical chains. Cd4V2Te 3O15 displays a second harmon- ic generation (SHG) efficiency of about 1.4 times that of KH2PO4 (KDP). Both compounds are direct band-gap semiconductors and are transparent in the range of 0.6- 10.0 mm. Measurements of lumines- cence indicate that both compounds exhibit broad emission bands in the blue-light region.

A lithium gadolinium phosphate crystal, LiGd5P2O13, has been synthesized by a high temperature solution reaction and solved by single-crystal X-ray diffraction data. The structure is monoclinic, space group C2/m, with unit cell parameters a = 18.645(3), b = 5.6257(5), c = 12.014(2) A, β = 117.55(6)°, V = 1117.3(3) A3, and Z = 4. LiGd5P2O13 presents a new structural type and is built up from [Gd5P2O13]- layers and one-dimensional Li chains with an unusual Li−Li distance. The optical properties were investigated in terms of the absorption and emission spectra. Additionally, the calculations of band structure, density of states, dielectric constants, and refractive indexes were performed with the density functional threory method. The obtained results tend to support the experimental data.

The structural, optical, and electronic properties of a series of lithium rare earth polyphosphates [LiLn(PO3)(4)] [Ln = La (1), Eu (2), Gd (3)] have been investigated by means of single-crystal X-ray diffraction, elemental analyses, and spectroscopic measurements, as well as calculations of energy-band structures, density of states, and optical response functions by density functional methods. These LiLn(PO3)(4) systems are monoclinic with space group C2/c and Z = 4. Their unit-cell parameters decrease as the ionic radius of Ln(3+) decreases (La3+ > Eu3+ > Gd3+). Both (PO4)(3-) zig-zag chains and infinite chains formed by the alternate connection of LnO(8) polyhedra and LiO4 tetrahedra run parallel to the b-axis in the structure. The energy-band structures, density of states, the chemical bonds, and optical properties have been investigated by density functional methods for some of the title compounds. (c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007.

An alkali metal-rare earth phosphate crystal of NaLa(PO3)4 has been synthesized by high temperature solid-state reactions and structurally characterized by single crystal X-ray diffraction analysis, for the first time. It crystallizes in the monoclinic P21/n space group with lattice parameters: a = 7.2655 ( 3 ) , b = 13.1952 ( 5 ) , c = 10.0760 ( 1 ) A , β = 90.382 ° ( 1 ) , V = 965.96 ( 5 ) A 3 , Z = 4 . It is composed of LaO8 polyhedra and [(PO3)4]4− chains sharing oxygen atoms to form a three-dimensional framework, delimiting intersecting tunnels in which the sodium ions are located. The IR spectrum, absorption spectrum, and emission spectrum of the compound have been investigated. The absorption edge is located at 340 nm (3.60 eV). The calculated total and partial densities of states indicate that the top of valence bands is mainly built upon O-2p states which interact with P-3p states via σ (P–O) interactions, and the low conduction bands mostly originates from unoccupied La-5d states. The P–O bond is mostly covalent in character, and the ionic character of the Na–O bond is larger than that in the La–O bond.

Ternary indium (III) phosphates with three-dimensional frameworks, [M{sub 3}In(PO{sub 4}){sub 2}]{sub n} (M=K, n=10; M=Rb, n=2), are found and firstly reported in this paper. These compounds have been obtained by high temperature solid-state reactions and their crystal structures have been determined by single crystal X-ray diffraction analysis. The title compounds, which crystallize in monoclinic system, possess the same [In(PO{sub 4}){sub 2}]{sub n}{sup 3n-} anionic frameworks built up from interconnected InO{sub 6} octahedra and PO{sub 4} tetrahedra and have an interesting tunnel structure where M{sup +} cations are located. Optical and bonding properties of [Rb{sub 3}In(PO{sub 4}){sub 2}]{sub 2} are investigated in terms of measured absorption and emission spectra, and calculated band structures and density of states. The crystal band structures obtained by the DFT method show that the solid compound of [Rb{sub 3}In(PO{sub 4}){sub 2}]{sub 2} is an insulator with direct band gap, and the P-O covalent bond characters are larger than the In-O ones in this compound.

Two compounds Zn3B2O6 and KZn4B3O9 were synthesized by high temperature solution reaction with different experiment routes from references. The crystal structure of Zn3B2O6 was refined and it crystallizes in monoclinic space group C 2 / c with cell dimensions a = 23.826 A , b = 5.4033 A , c = 8.3826 A , β = 102.912 , V = 981.8 A 3 and Z = 8 , μ = 14.494 cm −1 , D calcd = 4.245 g cm −3 . The UV–vis DRIS (ultraviolet–visible diffuse reflection integral spectrum), fluorescent spectra of two compounds have been studied. The calculated results of crystal energy band structure by the DFT method show that the solid state compounds of both Zn3B2O6 and KZn4B3O9 are isolators with direct band gaps. The calculated total and partial density of states indicate that the top valence bands are contributions from the mixings of O-2p, B-2p and Zn-3d states and low conduction bands mostly originate from Zn-4s states. The B O bonds are pure covalence and Zn O bonds are mostly ionic interactions, and the ionic interaction strength is stronger between the K O than between the Zn O in KZn4B3O9. The calculated optical response functions expect that these two compounds have width light transmission from the near ultraviolet (UV) to infrared (IR) light zone, and the average refractive index are 1.41 and 1.39 for Zn3B2O6 and KZn4B3O9 crystals, respectively.