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Synthesis, crystal structure and properties of [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} with mixed-valent Ge centers

One new manganese thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P2{sub 1}2{sub 1}2{sub 1} (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å{sup 3} and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge{sub 2}S{sub 4}]{sup 2−} anionic chain and a [(dien){sub 2}Mn]{sup 2+} complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1D [Ge{sub 2}S{sub 4}]{sup 2−} chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV–vis spectra. - Graphical abstract: One new thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4}, contains a one-dimensional [Ge{sub 2}S{sub 4}]{sup 2−} anionic chain with two different oxidation states of germanium centers. Display Omitted - Highlights: • One new manganese thiogermanate [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} was prepared. • The compound features 1D [Ge{sub 2}S{sub 4}]{sup 2−} chain composed of [Ge{sup II}S{sub 4}] and [Ge{sup IV}S{sub 4}] tetrahedra. • The first example of inorganic–organic hybrid thiogermanates with mixed valent Ge centers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Solvothermal syntheses, crystal structures, and properties of lanthanide(III) thioarsenates [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} (Ln==Sm, Eu, Gd) and [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] (Ln==Tb, Dy, Ho)

Solvothermal reactions of Ln{sub 2}O{sub 3}, As and S in diethylenetriamine (dien) at 170 °C for 6 days afforded two structural types of lanthanide thioarsenates with the general formulae [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} [Ln=Sm(1), Eu(2), Gd(3)] and [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] [Ln=Tb(4), Dy(5), Ho(6)]. The Ln{sub 2}O{sub 3} oxides were converted to [Ln(dien){sub 2}]{sup 3+} complex units in the solvothermal reactions. The As atom binds four S atoms, forming a tetrahedral AsS{sub 4} unit. In 1−3, the AsS{sub 4} units interconnect the [Ln(dien){sub 2}]{sup 3+} cations via Ln−S bonds as tridentate μ-1κ,2κ{sup 2}-AsS{sub 4} bridging ligands, resulting in the neutral coordination polymers [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} (Ln1). In 4−6, the AsS{sub 4} units coordinate with the Ln{sup 3+} ion of [Ln(dien){sub 2}]{sup 3+} as 1κ{sup 2}-AsS{sub 4} chelating ligands to form neutral coordination compounds [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] (Ln2). The Ln{sup 3+} ions are in nine- and eight-coordinated environments in Ln1 and Ln2, respectively. The formation of Ln1 and Ln2 is related with ionic size of the Ln{sup 3+} ions. Optical absorption spectra showed that 1−6 have potential use as semiconductors with the band gaps in the range 2.18−3.21 eV. - Graphical abstract: Two types of Ln-thioarsenates [Ln(dien){sub 2}(μ-1κ,2κ{sup 2}-AsS{sub 4})]{sub n} and [Ln(dien){sub 2}(1κ{sup 2}-AsS{sub 4})] were prepared by solvothermal methods and the soft Lewis basic AsS{sub 4}{sup 3–} ligand to Ln(III) centers with polyamine co-ligand was obtained. Display Omitted - Highlights: • Lanthanide thioarsenates were prepared by solvothermal methods. • The soft Lewis basic AsS{sub 4} ligand coordinate Ln{sup 3+} ions with coexistence polyamine ligands. • Two structural types of Ln-thioarsenates with structural turnover at Tb were obtained along Ln series. • The Ln-thioarsenates are potential semiconductors with optical band gaps in the range 2.18−3.21 eV.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Synthesis, characterization, and properties of the first indium borogermanate incorporating an organic amine ligand: InBGe{sub 2}O{sub 6}(OH){sub 2}(CH{sub 3}CH(NH{sub 2})CH{sub 2}NH{sub 2})·2H{sub 2}O

A new indium borogermanate incorporating an organic amine ligand, InBGe{sub 2}O{sub 6}(OH){sub 2}(CH{sub 3}CH(NH{sub 2})CH{sub 2}NH{sub 2})·2H{sub 2}O, was synthesized under solvothermal conditions and characterized by infrared spectroscopy, thermogravimetric analysis, and emission spectroscopy. This compound is a new example of the combination of metal, boron, and germanium atoms into one structure in the presence of organic amine molecules. Its 2D sheets with one 3-, one 4-, and two types of 6-membered rings consist of In{sub 2}O{sub 6}N{sub 4} octahedral dimers, Ge{sub 2}O{sub 6}(OH) double tetrahedra, and BO{sub 3}(OH) groups that are interconnected by water molecules to form a 3D supramolecular framework. Interestingly, the emission spectrum for this compound displays a strong broad band centered at 455 nm. - Graphical abstract: The first example of indium borogermanate incorporating an organic amine ligand was synthesized under solvothermal conditions. Infrared spectroscopy, thermogravimetric analysis, and emission spectroscopy have also been studied.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

A multi-functional coordination polymer coexisting spontaneous chirality resolution and weak ferromagnetism

A multifunctional homochiral coordination polymer, [Co(H{sub 2}O)(BDC)(4,4′-BPY)]∙3H{sub 2}O (1) (H{sub 2}BDC=1,2-benzenedicarboxylate and 4,4′-BPY=4,4′-bipyridine), has been successfully isolated from Co(II) ions and mixed ligands (1,2-benzenedicarboxylate and 4,4′-bipyridine). Complex 1, which exhibits spontaneous chirality resolution and weak ferromagnetism, is built by chiral helices interconnected via end-to-end 4,4′-BPY bridges into a two-dimensional (2D) layer structure. - Graphical abstract: A 2D cobalt coordination polymer compound showing spontaneous chirality resolution and weak ferromagnetism. - Highlights: • A new 2D cobalt mix-ligand coordination polymer complex has been synthesized. • The cobalt coordination polymer complex shows spontaneous chirality resolution in solid state. • The cobalt coordination polymer complex displays dominant and weak intrachain ferromagnetic interactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Oligomeric rare-earth metal cluster complexes with endohedral transition metal atoms

Comproportionation reactions of rare-earth metal trihalides (RX{sub 3}) with the respective rare-earth metals (R) and transition metals (T) led to the formation of 22 oligomeric R cluster halides encapsulating T, in 19 cases for the first time. The structures of these compounds were determined by single-crystal X-ray diffraction and are composed of trimers ((T{sub 3}R{sub 11})X{sub 15}-type, P6{sub 3}/m), tetramers ((T{sub 4}R{sub 16})X{sub 28}(R{sub 4}) (P-43m), (T{sub 4}R{sub 16})X{sub 20} (P4{sub 2}/nnm), (T{sub 4}R{sub 16})X{sub 24}(RX{sub 3}){sub 4} (I4{sub 1}/a) and (T{sub 4}R{sub 16})X{sub 23} (C2/m) types of structure) and pentamers ((Ru{sub 5}La{sub 14}){sub 2}Br{sub 39}, Cc) of (TR{sub r}){sub n} (n=2–5) clusters. These oligomers are further enveloped by inner (X{sup i}) as well as outer (X{sup a}) halido ligands, which possess diverse functionalities and interconnect like oligomers through i–i, i–a and/or a–i bridges. The general features of the crystal structures for these new compounds are discussed and compared to literature entries as well as different structure types with oligomeric T centered R clusters. Dimers and tetramers originating from the aggregation of (TR{sub 6}) octahedra via common edges are more frequent than trimers and pentamers, in which the (TR{sub r}) clusters share common faces. - Graphical abstract: Rare earth-metal cluster complexes with endohedral transition metal atoms (TR{sub 6}) may connect via common edges or faces to form dimers, trimers, tetramers and pentamers of which the tetramers are the most prolific. Packing effects and electron counts play an important role. - Highlights: • Rare-earth metal cluster complexes encapsulate transition metal atoms. • Oligomers are built via connection of octahedral clusters via common edges or faces. • Dimers through pentamers with closed structures are known. • Tetramers including a tetrahedron of endohedral atoms are the most prolific.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Synthesis, crystal structure and optical properties of two new layered cadmium iodates: Cd(IO{sub 3})X (X=Cl, OH)

Systematic explorations of new compounds in the cadmium iodate system by hydrothermal reactions led to two layered iodates, namely, Cd(IO{sub 3})X (X=Cl, OH). Cd(IO{sub 3})Cl crystallizes in the orthorhombic space group Cmca (No. 64) whereas Cd(IO{sub 3})(OH) crystallizes in the orthorhombic space group Pnma (No. 62). Cd(IO{sub 3})Cl displays a unique double layered structure composed of {sup 1}{sub ∞}[Cd−O{sub 3}Cl]{sub n} chains. Cadmium octahedrons form a 1D chain along the a-axis through edge sharing, and such chains are further interconnected via IO{sub 3} groups to form a special double layer on (020) plane. Cd(IO{sub 3})(OH) also exhibits a layered structure that is composed of cadmium cations, IO{sub 3} groups and hydroxyl ions. Within a layer, chains of CdO{sub 6} edge-shared octahedra are observed along the b-axis. And these chains are connected by IO{sub 3} groups into a layer parallel to the bc plane. Spectroscopic characterizations, elemental analysis, and thermogravimetric analysis for the reported two compounds are also presented. - Graphical abstract: Two new layered cadmium iodates Cd(IO{sub 3})X (X=Cl, OH) are reported. Cd(IO{sub 3})Cl features a unique double layered structure whereas Cd(IO{sub 3})(OH) displays an ordinary layered structure. - Highlights: • Two new layered cadmium iodates Cd(IO{sub 3})X (X=Cl, OH) are reported. • Cd(IO{sub 3})Cl features a unique double layered structure. • Cd(IO{sub 3})(OH) displays an ordinary layered structure. • The spectroscopic and thermal properties have been studied in detail.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

A combined experimental and theoretical study of the supramolecular self-assembly of Cu(II) malonate complex assisted by various weak forces and water dimer

A Cu(II) malonate complex with formula [Cu(C{sub 3}H{sub 2}O{sub 4})(C{sub 6}H{sub 8}N{sub 2})(H{sub 2}O)]{sub 2}·4H{sub 2}O (1) [C{sub 6}H{sub 8}N{sub 2}=2-picolylamine, C{sub 3}H{sub 2}O{sub 4}{sup 2−}=malonate dianion] has been synthesized by mixing the reactants in their stoichiometric proportion and its crystal structure has been determined by single-crystal X-ray diffraction. In 1, monomeric neutral metal malonate units [Cu(C{sub 3}H{sub 2}O{sub 4})(C{sub 6}H{sub 8}N{sub 2})(H{sub 2}O)] are interlinked with each other through hydrogen bonds, weak lone pair⋯π and cuprophilic interactions to generate supramolecular dimers, which in turn further associated through hydrogen bonding to form infinite 1D chains. Water dimers, through series of hydrogen bonds and weak π–stacking forces are found to be responsible for interconnection of 1D chains, which resulted in a 3D network. A density functional (DFT) study of the energetic features of several noncovalent interactions observed in the solid state have been analyzed and characterized using Bader's theory of “atoms-in-molecules”. We also present here Hirshfeld surface analysis to investigate the close intermolecular contacts. - Graphical Abstract: Interplay of weak forces like hydrogen bonding, lone pair⋯π, Cu⋯Cu and π–stacking interactions leading to the formation of supramolecular network in [Cu(C{sub 3}H{sub 2}O{sub 4})(C{sub 6}H{sub 8}N{sub 2})(H{sub 2}O)]{sub 2}·4H{sub 2}O complex. - Highlights: • A complex of Cu(II) with malonate and 2-picolylamine is synthesized and X-ray characterized. • We report a density functional study of the energetic features of several noncovalent interactions • We perform Hirshfeld surface analysis to investigate the close intermolecular contacts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Hydrothermal synthesis and characterization of the first mixed alkali borate-nitrate K{sub 3}Na[B{sub 6}O{sub 9}(OH){sub 3}]NO{sub 3}

The first mixed alkali borate-nitrate K{sub 3}Na[B{sub 6}O{sub 9}(OH){sub 3}]NO{sub 3} was synthesized under hydrothermal conditions from Na{sub 2}B{sub 4}O{sub 7}·10H{sub 2}O and K{sub 2}B{sub 4}O{sub 7}·4H{sub 2}O using KNO{sub 3} as a nitrate source. The compound crystallizes in the space group Pnnm (no. 58) with the lattice parameters a=1320.8(3), b=910.7(2), and c=1232.5(3) pm (Z=4). Isolated Sechserrings formed by BO{sub 4} and BO{sub 3} groups are linked through hydrogen bridges to form a three-dimensional network. - Graphical abstract: The first mixed alkali borate-nitrate K{sub 3}Na[B{sub 6}O{sub 9}(OH){sub 3}]NO{sub 3} was synthesized under hydrothermal conditions from Na{sub 2}B{sub 4}O{sub 7}·10H{sub 2}O and K{sub 2}B{sub 4}O{sub 7}·4H{sub 2}O using KNO{sub 3} as a nitrate source. - Highlights: • The first mixed alkali borate-nitrate K{sub 3}Na[B{sub 6}O{sub 9}(OH){sub 3}]NO{sub 3} is reported. • Hydrothermal conditions (240 °C, 3d) were used for the synthesis of K{sub 3}Na[B{sub 6}O{sub 9}(OH){sub 3}]NO{sub 3}. • Borate Sechserrings are interconnected through hydrogen-bonding.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

The magnetic and neutron diffraction studies of La{sub 1−x}Sr{sub x}MnO{sub 3} nanoparticles prepared via molten salt synthesis

Series of single-phase La{sub 1−x}Sr{sub x}MnO{sub 3} nanoparticles (x=0.25−0.47) with the size of about 50 nm was prepared in molten NaNO{sub 2}. TEM evidenced well dispersed particles that are not interconnected by sintering bridges in contrast to traditional products. Interestingly, some reduction of the perovskite cell volume, particularly at higher Sr-contents, was detected by XRD. Moreover, reduced magnetization and decreased Curie temperature in comparison to sol–gel samples were observed. Neutron diffraction analysis of the as-prepared nanoparticles and several comparative samples with x=0.37 indicated that the anomalous behavior of studied particles probably originate in the overdoped outer shell. The overdoping might result from both the surface oxygen chemisorption and from an increased Sr concentration in the shell. By all means, the overdoping would lead to compressive surface stress, driving the x=0.37 ground state toward a mixture of FM and A-type AFM ordering as observed by neutron diffraction. - Graphical abstract: La{sub 1−x}Sr{sub x}MnO{sub 3} nanoparticles with the size of about 50 nm were prepared by newly established method in molten NaNO{sub 2}. TEM proved the formation of well-separated particles without sintering bridges, the major advantage over traditional preparation methods. - Highlights: • Series of La{sub 1−x}Sr{sub x}MnO{sub 3} nanoparticles was prepared by novel method in NaNO{sub 2} melt. • Lower magnetization and Curie temperature in comparison to sol–gel nanoparticles was observed. • Overdoping of outer shell was indicated by neutron diffraction and cerimetric titration. • Overdoping shifts La{sub 0.37}Sr{sub 0.63}MnO{sub 3} ground state to a mixture of FM and A-type AFM ordering.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

The new silver borate Ag{sub 3}B{sub 5}O{sub 9}

Single crystals of Ag{sub 3}B{sub 5}O{sub 9} were obtained via high-pressure synthesis at 3 GPa and 600 °C, using a Walker-type multianvil high-pressure device. Ag{sub 3}B{sub 5}O{sub 9} crystalizes with a=674.7(2), b=943.5(2), c=1103.5(2) pm, V=0.7025(2) nm{sup 3}, and Z=4 in the noncentrosymmetric space group P2{sub 1}2{sub 1}2{sub 1} (no. 19). The orthorhombic structure was refined from 3740 independent reflections with R1=0.0496 and wR2=0.587 (all data). It is built up from infinite corner-sharing chains of BO{sub 4} tetrahedra along the a axis, which are interconnected by BO{sub 3} groups to form a network. In the structure, three crystallographically independent sites are occupied with Ag{sup +} cations exhibiting argentophillic interactions. The synthetic conditions as well as the results of the single crystal structure analysis are presented. - Graphical abstract: Noncentrosymmetric silver borate: During investigations in the system Ag–B–O, a new noncentrosymmetric silver borate Ag{sub 3}B{sub 5}O{sub 9} was discovered. The new structure type is built up from corner-sharing BO{sub 3} and BO{sub 4} groups, forming a network. Argentophillic interactions are clearly indicated by the Ag{sup +}⋯Ag{sup +} distances present in the structure. - Highlights: • A noncentrosymmetric borate Ag{sub 3}B{sub 5}O{sub 9} is accessible via high-pressure synthesis. • Ag{sub 3}B{sub 5}O{sub 9} is the second high-pressure silver borate. • Ag{sup +}⋯Ag{sup +} distances in Ag3B5O9 clearly indicate the presence of argentophillic interactions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

High pressure structural behavior of YGa{sub 2}: A combined experimental and theoretical study

High pressure structural stability studies were carried out on YGa{sub 2} (AlB{sub 2} type structure at NTP, space group P6/mmm) up to a pressure of ~35 GPa using both laboratory based rotating anode and synchrotron X-ray sources. An isostructural transition with reduced c/a ratio, was observed at ~6 GPa and above ~17.5 GPa, the compound transformed to orthorhombic structure. Bulk modulus B{sub 0} for the parent and high pressure phases were estimated using Birch–Murnaghan and modified Birch–Murnaghan equation of state. Electronic structure calculations based on projector augmented wave method confirms the experimentally observed two high pressure structural transitions. The calculations also reveal that the ‘Ga’ networks remains as two dimensional in the high pressure isostructural phase, whereas the orthorhombic phase involves three dimensional networks of ‘Ga’ atoms interconnected by strong covalent bonds. - Graphical abstract: High pressure X-ray diffraction patterns of YGa{sub 2} up to ~35 GPa shows an isostructural phase transition at ~5 GPa and transition to an orthorhombic structure ~14 GPa. - Highlights: • High pressure structural stability studies were carried out on YGa{sub 2} up to 35 GPa. • An isostructural transition with reduced c/a ratio was observed above 6 GPa. • Above 17.5 GPa, the compound transformed to orthorhombic structure. • PAW based electronic structure calculations have been carried out. • Calculations confirm the experimentally observed structural transitions.

36 MATERIALS SCIENCE↗

In situ ligand generation for novel Mn(II) and Ni(II) coordination polymers with disulfide ligand: Solvothermal syntheses, structures and magnetic properties

Two coordination polymers, ([Mn{sub 2}(L1){sub 2}(μ{sub 2}-H{sub 2}O)(H{sub 2}O){sub 4}]·5H{sub 2}O){sub n}1 and ([Ni(L1)(H{sub 2}O){sub 2}]·2H{sub 2}O){sub n}2 (H{sub 2}L1=2,2′-dithiobisnicotinic acid), were prepared by the solvothermal reactions of the Mn(II) or Ni(II) ions with 2-mercaptonanicotinic acid. In 1, the [Mn{sub 2}(COO){sub 4}] units are connected by the 2,2′-dithiobisnicotinic dianion to form a two-dimensional (4,4)-connected network. In 2, the adjacent Ni(II) ions are connected by the carboxyl groups of the 2,2′-dithiobisnicotinic dianion to form an one-dimensional inorganic rod-shaped chain [Ni(COO){sub 2}]{sub n}, which are further interconnected by the 2,2′-dithiobisnicotinic ligand, giving rise to a two-dimensional framework. Variable-temperature magnetic susceptibilities of 1 and 2 exhibit overall weak antiferromagnetic coupling between the adjacent metal ions. - Graphical abstract: Two 2D coordination polymers were synthesized by transition-metal/in-situ oxidation of 2-mercaptonicotinic acid. The compounds pack into 2D frameworks by the carboxyl groups of 2,2′-dithiobisnicotinic dianion and exhibit overall weak antiferromagnetic coupling. - Highlights: • Two 2D coordination polymers containing 2,2′-dithiobisnicotinic dianion. • In situ oxidation and dehydro coupling reaction of 2-mercaptonbenzoic acid. • Two compounds display weak antiferromagnetic exchanges.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Ultra-flexible framework breathing in response to dehydration in liskeardite, [(Al,Fe){sub 16}(AsO{sub 4}){sub 9}(OH){sub 21}(H{sub 2}O){sub 11}]·26H{sub 2}O, a natural open-framework compound

Dehydration of the natural open-framework compound, liskeardite, [(Al,Fe){sub 16}(AsO{sub 4}){sub 9}(OH){sub 21}(H{sub 2}O){sub 11}]·26H{sub 2}O, is accompanied by a change in the sign of the thermal expansion from positive to negative above room temperature, and at ~100 °C the structure undergoes a dramatic 2D contraction by co-operative rotation of heteropolyhedral columns that constitute the framework walls. Monoclinic liskeardite, I112 with a≈b≈24.7 Å, c ≈7.8 Å and β≈90° is transformed to a tetragonal phase, I-4 with a≈20.6 Å, c ≈7.7 Å. The associated 30% decrease in volume is unprecedented in inorganic microporous compounds. The flexibility of the contraction is related to the double-hinged nature of the column rotations about [001]. Octahedra in adjacent columns are interconnected by corner-sharing with the two pairs of anions forming opposing edges of AsO{sub 4} tetrahedra, so a double-hinged rotation mechanism operates. Thermal analysis and mass spectroscopic results for liskeardite show that the phase transition at ~100 °C is related to removal of the channel water. The tetragonal phase shows exceptionally large NTE behaviour. Over the temperature range 148–178 the NTE along a and b is close to linear with a magnitude of the order of −900×10{sup −6} °C{sup −1}. The contraction along the channel direction is smaller but still appreciable at −200×10{sup −6} °C{sup −1}. - Graphical abstract: Structure of the collapsed liskeardite framework, formed on dehydration above 100 °C. - Highlights: • The thermal expansion of the mineral liskeardite changes + to − above ambient. • Dehydration at 100 °C results in a record reversible 30% volume reduction. • In situ synchrotron XRD has led to a structural model for the dehydrated phase. • Framework breathing flexibility is attributed to a double-hinge rotation mechanism. • The dehydrated phase shows unprecedented -ve expansion for inorganic materials.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Synthesis, crystal structures and properties of lead phosphite compounds

Here, we report the preparation and characterization of two lead(II) phosphites, namely, Pb{sub 2}(HPO{sub 3}){sub 2} and Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} through hydrothermal reaction or simple solution synthesis, respectively. A new lead phosphite, namely, Pb{sub 2}(HPO{sub 3}){sub 2}, crystallizes in the noncentrosymmetric space group Cmc2{sub 1} (no. 36), which features 3D framework formed by the interconnection of 2D layer of lead(II) phosphites and 1D chain of [Pb(HPO{sub 3}){sub 5}]{sub ∞}. The nonlinear optical properties of Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} have been studied for the first time. The synergistic effect of the stereo-active lone-pairs on Pb{sup 2+} cations and π-conjugated NO{sub 3} units in Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} produces a moderate second harmonic generation (SHG) response of ∼1.8×KDP (KH{sub 2}PO{sub 4}), which is phase matchable (type I). IR, UV–vis spectra and thermogravimetric analysis (TGA) for the two compounds were also measured. - Graphical abstract: Two lead phosphites Pb{sub 2}(HPO{sub 3}){sub 2} and Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} are studied. A new lead phosphite Pb{sub 2}(HPO{sub 3}){sub 2} features a unique 3D framework structure and Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} shows a moderate SHG response of ∼1.8×KDP (KH{sub 2}PO{sub 4}). - Highlights: • A new lead phosphite, Pb{sub 2}(HPO{sub 3}){sub 2} is reported. • Pb{sub 2}(HPO{sub 3}){sub 2} features a unique 3D framework structure. • NLO property of Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} is investigated. • Pb{sub 2}(HPO{sub 3})(NO{sub 3}){sub 2} produces a moderate SHG response of ∼1.8×KDP (KH{sub 2}PO{sub 4}).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Structural diversification and photocatalytic properties of three Cd(II) coordination polymers decorated with different auxiliary ligands

Three cadmium coordination polymers, [Cd(bismip)]{sub n} (1), {[Cd(bismip)(phen)]·H_2O}{sub n} (2) and {[Cd_2(bismip)_2(4,4′-bipy)]·2H_2O}{sub n} (3) (H{sub 2}bismip=5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid, phen=1,10-phenanthroline, 4,4′-bipy=4,4′-bipyridine) have been prepared under solvothermal conditions. In 1, the [Cd{sub 4}(bismip){sub 3}] units are jointed by bismip ligands to afford a three-dimensional (3D) architecture. Complex 2 exhibits a 3D supramolecular framework based on the interconnection of 1D chains through hydrogen bonding interactions and π-π packing interactions. 3 is a two-fold interpenetrating 3D architecture with a (4·8{sup 2})(4{sup 2}·8{sup 4}) Schläfli symbol in which 2D layers are interlinked by 4,4′-bipy ligands. The diverse structures of compounds 1–3 indicate that the auxiliary ligands have significant effects on the final structures. The photoluminescent properties and photocatalytic properties of these coordination polymers in the solid state were also investigated. Remarkably, 3 shows the wide gap semiconductor nature and exhibit excellent photocatalytic performance. - Graphical abstract: Three cadmium coordination polymers with different architectures based on 5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid have been prepared. Their photoluminescent properties were also investigated. - Highlights: • Three new Cd(II) Cps were synthesized based on H{sub 2}bismip. • Compounds 1 and 3 show 3D networks and 2 exhibits a 1D chain. • Compoud 3 exhibits good catalytic activity of methylene blue photodegradation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Synthesis, structural characterization, Hirshfeld surface analysis and spectroscopic studies of cadmium (II) chloride complex with 4-hydroxy-1-methylpiperidine

The chemical preparation, crystal structure, Hirshfeld surface analysis and spectroscopic characterization of the novel cadmium (II) 4-hydroxy-1-methylpiperidine complex, Cd{sub 4}Cl{sub 10}(C{sub 6}H{sub 14}NO){sub 2}·2H{sub 2}O, have been reported. The atomic arrangement can be described as built up by an anionic framework, formed by edge sharing CdCl{sub 6} and CdCl{sub 5}O octahedral linear chains spreading along the a-axis. These chains are interconnected by water molecules via O–H⋯Cl and O–H⋯O hydrogen bonds to form layers parallel to (011) plane. The organic cations are inserted between layers through C–H⋯Cl hydrogen bonds. Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analysis reveals that the H{sub C}⋯Cl and H{sub C}⋯H{sub C} intermolecular interactions are the most abundant contacts of the organic cation in the crystal packing. The statistical analysis of crystal contacts reveals the driving forces in the packing formation. The {sup 13}C and {sup 15}N CP-MAS NMR spectra are in agreement with the X-ray structure. The vibrational absorption bands were identified by infrared spectroscopy. DFT calculations allowed the attribution of the NMR peaks and of the IR bands.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Syntheses, structures and characterizations of three novel vanadium selenites with organically bonded copper/nickel complex

A series of vanadium selenites covalently bonded with metal-organic complex, namely, Ni(2,2-bipy){sub 2}V{sub 2}O{sub 4}(SeO{sub 3}){sub 2} (1), Cu(2,2-bipy)V{sub 2}O{sub 4}(SeO{sub 3}){sub 2}·0.5H{sub 2}O (2) and Cu{sub 2}(2,2-bipy){sub 2}V{sub 5}O{sub 12}(SeO{sub 3}){sub 2} (3) (2,2-bipy=2,2-bipyridine) have been hydrothermally synthesized and structurally characterized. They exhibit three different structural dimensions, from 0D cluster, 1D chain to 2D layer. Compound 1 features a 0D {Ni(2,2-bipy)_2V_2O_4(SeO_3)_2}{sub 2} dimeric cluster composed of two {Ni(2,2-bipy)_2}{sup 2+} moieties connected by the {V_4O_8(SeO_3)_4}{sup 4-} cluster. Compound 2 shows a 1D {Cu(2,2-bipy)V_2O_4(SeO_3)_2}{sub n} chain in which the {Cu_2(2,2-bipy)_2}{sup 4+} moieties are bridged by the {V_4O_8(SeO_3)_4}{sup 4−} clusters. Compound 3 displays a 2D structure consisted of mixed valence vanadium selenites layers {V"I"VV"V_4Se"I"V_2O_1_8}{sub n}{sup 4−} and {Cu(2,2-bipy)}{sup 2+} complex moieties. The adjacent layers are further interconnected via π-π interactions between the 2,2-bipy ligands exhibiting an interesting 3D supramolecular architecture. Both compound 1 and 2 contain a new {V_4O_8(SeO_3)_4}{sup 4−} cluster and compound 3 exhibits the first 2D vanadate polyhedral layer in vanadium selenites/tellurites with organic moieties. - Graphical abstract: We got three new vanadium selenites with organically linked copper/nickel complex, namely, Ni(2,2-bipy){sub 2}V{sub 2}O{sub 4}(SeO{sub 3}){sub 2} (1), Cu(2,2-bipy)V{sub 2}O{sub 4}(SeO{sub 3}){sub 2}·0.5H{sub 2}O (2) and Cu{sub 2}(2,2-bipy){sub 2}V{sub 5}O{sub 12}(SeO{sub 3}){sub 2} (3) by hydrothermally syntheses. They display three different structural dimensions, from 0D cluster, to 1D chain and 2D layer. Display Omitted - Highlights: • Three new compounds display three different structural dimensions, from 0D cluster, to 1D chain and 2D layer. • The Tetranuclear {V_4O_8(SeO_3)_4}{sup 4−} cluster and the vanadate {V_5O_1_7}{sub n} 2D layer are observed firstly. • Optical Properties and Magnetic Properties of three compounds are reported.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Synthesis, crystal structure, electrical properties, and sodium transport pathways of the new arsenate Na{sub 4}Co{sub 7}(AsO{sub 4}){sub 6}

A new sodium cobalt (II) arsenate Na{sub 4}Co{sub 7}(AsO{sub 4}){sub 6} has been synthesized by a solid-state reaction and its crystal structure determined from single crystal X-ray diffraction data. It crystallizes in the monoclinic system, space group C2/m, with a=10.7098(9) Å, b=14.7837(9) Å, c=6.6845(7) Å, and β=105.545(9)°. The structure is described as a three-dimensional framework built up of corner-edge sharing CoO{sub 6}, CoO{sub 4} and AsO{sub 4} polyhedra, with interconnecting channels along [100] in which the Na{sup +} cations are located. The densest ceramics with relative density of 94% was obtained by ball milling and optimization of sintering temperature, and its microstructure characterized by scanning electron microscopy. The electrical properties of the ceramics were studied over a temperature interval from 280 °C to 560 °C using the complex impedance spectroscopy over the range of 13 MHz–5 Hz. The ionic bulk conductivity value of the sample at 360 °C is 2.51 10{sup −5} S cm{sup −1} and the measured activation energy is Ea=1 eV. The sodium migration pathways in the crystal structure were investigated computationally using the bond valence site energy (BVSE) model and classical molecular dynamics (MD) simulations. - Graphical abstract: Correlation between crystal structure, microstructure and ionic conductivity . Display Omitted - Highlights: • A new arsenate Na{sub 4}Co{sub 7}(AsO{sub 4}){sub 6} was prepared by solid state reaction. • Its crystal structure was determined by powder X-ray diffraction. • Na{sup +} ionic conductivity was probed by complex impedance spectroscopy. • Na{sup +} conduction pathways were modeled by bond-valence method and molecular dynamics.

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