Robert Glaum

University of Bonn | Uni Bonn · Institute for Inorganic Chemistry

he Cover Feature shows a 3D view of the single-crystal structure of K3[MO4][MO3N] with M=Tc, Re together with the Raman spectrum of K3[ReO4][ReO3N]. Both compounds were synthesized using a highly alkaline KOH hydroflux. Since single-crystal X-ray diffraction does not prove the presence of nitrogen within the (MO4)-tetrahedra unambiguously, Raman an...

The reactions of ammonium perrhenate and pertechnetate in highly alkaline medium led to the isotypic mixed anionic nitridotrioxidorhenate and -technetate K3[MO4][MO3N] (M= Tc, Re). Both compounds occur as colorless crystals, which were investigated by single crystal X-ray diffraction. Furthermore, K3[ReO4][ReO3N] has been studied by means of X-ray...

Phosphate tungsten and molybenum bronzes represent an outstanding class of materials displaying textbook examples of charge-density-wave (CDW) physics among other fundamental properties. Here we report on the existence of a novel structural branch with the general formula [Ba(PO4)2][W3O3-m] (m = 3, 4 and 5) denominated 'layered monophosphate tungst...

Phosphate tungsten and molybenum bronzes represent an outstanding class of materials displaying textbook examples of charge‐density‐wave (CDW) physics among other fundamental properties. Here we report on the existence of a novel structural branch with the general formula [Ba(PO 4 ) 2 ][W m O 3 m −3 ] ( m =3, 4 and 5) denominated ′ layered monophos...

Related Article: Niobium Insertion into αII-VOPO4: Tuning the Catalytic Properties for Selective Oxidation (https://doi.org/10.1021/acscatal.2c06209) In this work, catalyst design rules for improved selective oxidations are derived from the study of (V1‑xNbx)OPO4, a bulk material with tunable catalytic properties in n-butane oxidation. Clear prope...

The hydrogensulfate‐sulfates Ln(HSO4)(SO4) (Ln: Sm, Eu, Gd, Tb, Dy) have been crystallized from sulfuric acid and their thermal decomposition behavior has been studied. The crystal structures for all members of the series were refined from X‐ray single‐crystal diffraction data (for all: Tb(HSO4)(SO4) structure type, P21, Z = 2, a ≈ 6.66 Å, b ≈ 6.63...

Objectives To evaluate and compare fracture resistance, translucency, and color reproducibility, as well as the effect of aging on the fracture load and color stability of novel monolithic CAD/CAM ceramics. Materials and methods One hundred crowns of uniform thickness were milled from five ceramic blocks ( n = 20): partially crystallized lithium d...

Platinum group metal (PGM)-based catalysts are known to be highly active in the total combustion of lower hydrocarbons. However, through an alternative catalyst design reported in this paper by isolating PGM-based active sites in a tungsten phosphate matrix, we present a class of catalysts for selective oxidation of n-butane, propane, and propylene...

The mixed‐valent, formerly unknown europium borate Eu 5 (BO 3 ) 4 was synthesized from various starting materials. Its structure was refined by Rietveld analysis. Eu 5 (BO 3 ) 4 crystallizes in space group Pnma ( a = 2229.77(2) pm, b = 1599.91(2) pm, and c = 877.75(1) pm) and was found to be isostructural with Eu 5 (BO 2.51 N 0.49 ) 4 . Powder refl...

OsP2O7 with cubic (ZrP2O7 type, Z = 4, a = 7.8276(4) Å, 3x3x3 superstructure with a ’ = 3a = 23.484(2) Å) and triclinic symmetry (ruby‐red crystals, SXRD study, GeP2O7 type, [[EQUATION]] (no. 2), Z = 2, a = 4.8072(7) Å, b = 6.8993(13) Å, c = 8.0502(10) Å, α = 91.819(16)°, β = 92.921(14)°, γ = 107.415(15)°, 98 param., R1 = 0.045, wR2 = 0.144, 3006 u...

Two thermodynamically metastable polymorphs of vanadium(III) phosphate, VIIIPO4-m1 and VPO4-m2, have been obtained via reduction of β-VVOPO4 by moist hydrogen. The XRPD pattern of VPO4-m1 can be assigned based on the crystal structure of β-VVOPO4, though with distinctly different lattice parameters (VPO4-m1/β-VOPO4: Pnma, a = 7.3453(12)/7.7863(5) Å...

Solution combustion synthesis followed by annealing in air led to the MPTB‐related phosphates (Rh1/6W5/6O3)8(PO2)4, (Ir1/6W5/6O3)8(PO2)4 (a = 5.258(2) Å, b = 6.538(3) Å, c = 17,322(8) Å), (Rh1/9W8/9O3)12(PO2)4 and (Rh2/21W19/21O3)14(PO2)4. Single‐crystals of the mixed‐metal (Rh,W)‐MPTBs at m = 4 and at m = 7 were grown by chemical vapor transport (...

Powder reflectance spectra and temperature dependent magnetic susceptibilities of SmP5O14, SmPO4, SmVO4, SmNbO4, SmTaO4, Sm2Ti2O7, SmAsO 4, B‐type Sm2O 3 and C‐type Sm2O3 have been measured. In addition, high‐resolution electronic NIR absorption spectra of single crystals of seven of these compounds are reported. Comparing our experimental data to...

Different structure types of vanadyl(V) orthophosphate [i.e. (V V ≡O) ³⁺ orthophosphate] have been subjects of research due to their catalytic activity in the oxidation of n -butane to maleic anhydride. Electron paramagnetic resonance (EPR) spectroscopy can be exploited to elucidate the electronic structure of such compounds. When tuning the oxidat...

Increased synthetic control in borosulfate chemistry leads to the access of various new compounds. Herein, we unravel the polymorphism for phyllosilicate‐analogous borosulfates by adjusting the oleum (65% SO 3 ) content. The new polymorphs β‐Mg[B 2 (SO 4 ) 4 ] and α‐Co[B 2 (SO 4 ) 4 ] both consist of similar layers of alternating borate and sulfate...

The monoclinic α -polymorph of (V IV O)(PO 3 ) 2 is obtained reproducibly by reaction of V 2 O 5 and H 3 PO 4 (85%) (Au crucible, 380 °C, 4 d). Its crystal structure was refined from X-ray single-crystal data [ C 2/c, Z = 4, a = 15.1038(7) Å, b = 4.193(2) Å, c = 9.573(9) Å, β = 126.45(3), R 1 = 0.052, wR 2 = 0.189 for 976 unique reflections with F...

Electronic properties of V2OPO4 have been investigated by means of hard x-ray photoemission spectroscopy (HAXPES) and subsequent theoretical calculations. The V 1s and 2p HAXPES spectra are consistent with the charge ordering of V2+ and V3+. The binding energy difference between the V2+ and V3+ components is unexpectedly large, indicating large bon...

Electronic properties of V2OPO4 have been investigated by means of hard x-ray photoemission spectroscopy (HAXPES) and subsequent theoretical calculations. The V 1$s$ and 2$p$ HAXPES spectra are consistent with the charge ordering of V$^{2+}$ and V$^{3+}$. The binding energy difference between the V$^{2+}$ and V$^{3+}$ components is unexpectedly lar...

V 3d charge and orbital states in V2OPO4 have been investigated by means of x-ray absorption spectroscopy (XAS). The electronic structure of V2OPO4 is very unique in that the charge transfer between V2+ and V3+ in face-sharing VO6 chains provides negative thermal expansion as reported by E. Pachoud et al. [J. Am. Chem. Soc. 140, 636 (2018)]. The ne...

Negative volume expansion between 620 and 800 K in V2OPO4 is discovered to be of electronic origin due to the charge ordering transition at 605 K. Domain reorientation and coexistence...

Optical spectra (powder reflectance, UV/vis/NIR region), and temperature dependent magnetic behavior (χ, μ/μ B ) have been recorded for the series of anhydrous europium(III) phosphates Eu III 3 O 3 (PO 4 ), Eu III PO 4 , Eu III 2 P 4 O 13 , lt ‐ and ht ‐Eu III (PO 3 ) 3 , and Eu III P 5 O 14 . By modeling within the AOM framework, the experimental...

V 3$d$ charge and orbital states in V$_2$OPO$_4$ have been investigated by means of x-ray absorption spectroscopy (XAS). The electronic structure of V$_2$OPO$_4$ is very unique in that the charge transfer between V$^{2+}$ and V$^{3+}$ in face sharing VO$_6$ chains provides negative thermal expansion as reported by Pachoud et al. [J. Am. Chem. Soc....

Polycrystalline samples of La- and Lu-agardite with the composition RE Cu 6 (OH) 6 (AsO 4 ) 3 · n H 2 O ( RE = La, Lu; n ≈3) have been prepared and the structure of the products was determined by X-ray powder diffraction studies. The characterization has been complemented by Raman and UV/Vis spectroscopic, magnetic and TGA investigations. DFT calcu...

The vanadyl pyrophosphate (VPP) based catalyst is unique in converting n-butane selectively (60–70%) into maleic anhydride (MAN), whereas a MAN selectivity of 20% may be regarded as high for structurally different catalyst systems. We present novel vanadium phosphorus oxides and mixed metal phosphate solid solutions tested for n-butane oxidation to...

3d transition metal nitridophosphates MIIP8N14 (MII = Fe, Co, Ni) were prepared by high‐pressure metathesis indicating that this route might give a systematic access to a structurally rich family of M‐P‐N compounds. Their structures, which are stable in air up to at least 1273 K, were determined through powder X‐ray diffraction and consist of highl...

3d transition metal nitridophosphates MIIP8N14 (MII = Fe, Co, Ni) were prepared by high‐pressure metathesis indicating that this route might give a systematic access to a structurally rich family of M‐P‐N compounds. Their structures, which are stable in air up to at least 1273 K, were determined through powder X‐ray diffraction and consist of highl...

By quenching a melt of Li4P2O7 two new, thermody‐namically metastable polymorphs are obtained as biphasic mixtures. The crystal structure of one polymorph was determined from single‐crystal X‐ray diffraction data {Li4P2O7‐trig*: colourless, trigonal, P3212 (no. 153), Z = 3, a = 5.1699(2) Å, c = 18.9722(8) Å, 60 parameters, R1 = 0.018, wR2 = 0.051,...

The reaction network of n-butane selective oxidation was comparatively analyzed over a novel αII-V0.8W0.2OPO4 orthophosphate and a reference vanadyl pyrophosphate (VPP) based catalyst via parameter field studies (T = 360–420 °C, x(n-butane) = 0.5–2.0%, x(O2) = 10–20%) as well as cofeed and pulse experiments with presumed reaction intermediates. For...

In the ternary system Eu/P/O the anhydrous phosphates EuII3(PO4)2, EuII3EuIII(PO4)3, EuIII3O3(PO4), EuIIIPO4, EuIII(PO3)3, and EuIIIP5O14 exist at equilibrium conditions (ϑ ≈ 1000 °C). A superstructure model for EuII3EuIII(PO4)3 [Eulytite structure family, Fdd2, Z = 24, a = 14.298(1) Å, b = 42.123(3) Å, c = 10.3887(9) Å] is proposed. The results of...

Mechanochemistry enabled the selective synthesis of the orange polymorph of Wilkinson’s catalyst [RhCl(PPh3)3]. The mechanochemically prepared Rh-complex catalysed the solvent-free dehydrogenation of Me2NH·BH3 in a ball mill. The in situ-generated...

By dehydration of the known coordination polymers 1∞[MII(tF‐BDC)(H2O)4] (MII = Co2+, Zn2+ and tF‐BDC2– = tetrafluoroterephthalate) the homoleptic anhydrous coordination networks 3∞[MII(tF‐BDC)] were obtained as polycrystalline powders. Their crystal structures (C2/c, Z = 4) were solved and refined by means of synchrotron powder diffraction data. Th...

Ag6(VIVO)2(PO4)2(P2O7) has been obtained by reaction of Ag3PO4 and (VO)2P2O7 (sealed ampoule, 550 °C, 3d). The crystal structure of the new mixed ortho‐pyrophosphate has been determined from X‐ray single‐crystal data (Pnma, Z = 4, a = 12.759(3) Å, b = 17.340(4) Å, c = 6.418(1) Å, R1 = 0.071, wR2 = 0.184 for 3174 unique reflections with Fo > 4σ(Fo),...

The program BonnMag has been developed to calculate the absorption spectra and temperature dependent magnetic susceptibilities of f ⁿ systems. The computations of the transition energies are performed within the angular overlap model. Using Judd–Ofelt theory BonnMag allows estimation of the relative absorption coefficients of the electronic transit...

Coordination or local environments (e.g., tetrahedra and octahedra) are powerful descriptors of the crystalline structure of materials. These structural descriptors are essential to the understanding of crystal chemistry and the design of new materials. However, extensive statistics on the occurence of local environment are not available even on co...

By means of chemical vapor transport reactions ( CVT ) a variety of solid‐state compounds can be prepared, mostly as impurity free single crystals. Representatives are well‐established for elements, intermetallics, halides, oxides, sulphides, selenides, tellurides, pnictides, and so on. The fundamental thermodynamic principles of CVT reactions are...

The europium-oxygen interaction in nine different europium(III) oxo-compounds (including C-type Eu2O3) was investigated on the basis of powder reflectance spectra (near-IR/vis/UV) and temperature-dependent magnetic measurements. Computation of the transition energies and of the effective Bohr magneton numbers for Eu(3+) in the different ligand fiel...

γ-NiB4O7 was synthesized in a high-pressure/high-temperature experiment at 5 GPa and 900 °C. The single-crystal structure analysis yielded the following results: space group P6522 (No. 179), a = 425.6(2), c = 3490.5(2) pm, V = 0.5475(2) nm(3), Z = 6, and Flack parameter x = -0.010(5). Second harmonic generation measurements confirmed the acentric c...

Titanium(III) phosphate, TiPO4 , is a typical example of an oxyphosphorus compound containing covalent P-O bonds. Single-crystal X-ray diffraction studies of TiPO4 reveal complex and unexpected structural and chemical behavior as a function of pressure at room temperature. A series of phase transitions lead to the high-pressure phase V, which is st...

Titanium(III) phosphate, TiPO4 , is a typical example of an oxyphosphorus compound containing covalent P−O bonds. Single-crystal X-ray diffraction studies of TiPO4 reveal complex and unexpected structural and chemical behavior as a function of pressure at room temperature. A series of phase transitions lead to the high-pressure phase V, which is st...

Emerald-green single crystals of U(PO4)Cl are prepared by chemical vapor transport in a temperature gradient of 1000 900 °C from a stoichiometric mixture of UP2O7, UO2, and ZrCl4.

Detailed experimental data on UPO4Cl comprising single-crystal UV/vis/NIR spectra and temperature-dependent magnetic susceptibilities form the basis for the investigation of the electronic structure of the U(4+) cation in UPO4Cl. For modeling of the observed physical properties the angular overlap model (AOM) was successfully employed. The computat...

Emerald-green single crystals of U(PO4)Cl were grown by chemical vapor transport in a temperature gradient (1000 → 900 °C). The crystal structure of U(PO4)Cl (Cmcm, Z = 4, a = 5.2289(7) Å, b = 11.709(2) Å, c = 6.9991(8) Å) consists of a three-dimensional network of [PO4] tetrahedra and bicapped octahedral [U(IV)O6Cl2] groups. Polarized absorption s...

A series of hitherto unknown mixed-metal phosphates of the monophosphate tungsten bronze structure family [MPTB; (WO3)2m(PO2)4] have been obtained by solution combustion synthesis followed by annealing (ϑ = 850°C) at appropriate oxygen pressures. These new phosphates show substitution of W5+ by either M3+1/3W6+2/3 (M: V, Cr, Fe, Mo) or Ti4+1/2W6+1/...

In this work we present the synthesis and characterization of the first mixed-valent, purely cobalt-based zeolitic imidazolate framework, CoII3CoIII2(C3H3N2)12. The material adopts the cubic garnet-type structure and combines high thermal stability of up to 350 °C with excellent chemical stability. Electrochemical characterization shows that the co...

The series of isotypic anhydrous ortho-pyrophosphates MIII(WVIO2)2(P2O7)(PO4) (M: Sc, V, Cr, Fe, Mo, Ru, Rh, In, Ir) was obtained via vapor phase moderated solid state reactions in sealed ampoules. The crystal structure of the phosphates MIII(WVIO2)2(P2O7)(PO4) (M: V, Ru, Rh) was solved from single crystal X-ray data (C2/c, Z 1/4 16). Fairly regula...

The surprisingly complicated crystal structure of (bis(terpyridine))copper(II) tetraphenylborate [Cu(tpy)2](BPh4)2 (tpy = 2,2':6',2″-terpyridine) consists of six crystallographically independent [Cu(tpy)2](2+) complexes. At ambient temperature, five out of six [Cu(II)N6] chromophores appear to be compressed octahedra, while at 100 K, four exhibit e...

The solid solutions (V1-xWx)OPO4 with β-VOPO4 structure (0.0 ≤ x ≤ 0.01) and αII-VOPO4 (tetragonal space group P4/n, Z = 2) structure (0.04 ≤ x ≤ 0.26) are obtained from mixtures of VOPO4 and WOPO4 by conventional solid state reaction in the presence of Cl2 as mineralizer (silica ampoule, 800 °C, 7 d).

The new compounds LiCrII4(PO4)3 (I) and Li5CrII2CrIII (PO4)4 (II) in the Li/Cr/P/O system are prepared from stoichiometric mixtures of Li3PO4, CrPO4, and Cr using iodine as mineralizer (sealed silica tubes, 800 °C, 7 d).

The two new phosphates LiCrII4(PO4) 3 and Li5CrII2Cr III(PO4)4 are discovered as equilibrium phases (δ=800 °C) in the quarternary system Li/Cr/P/O. Their crystal structures have been determined from single-crystal X-ray diffraction data {LiCrII4(PO4)3: violet-blue, Pnma (no. 62), Z=4, a=6.175(1) Å, b=14.316(3) Å, c=10.277(2) Å, 100 parameters, R1=0...

The monoclinic form of Li3Cr2(PO4)3 is galvanostatically cycled in a half cell versus lithium as anode. For the first time active redox behaviour of trivalent chromium in a phosphate matrix at around 4.8 V vs. Li+/Li is demonstrated. The coulombic efficiency ideally approaches 80%. Based on extensive XPS analyses, a possible oxidation scenario is s...

The solid solutions (V1–xWx)OPO4 with β-VOPO4 structure type (0.0 ≤ x ≤ 0.01) and αII-VOPO4 structure type (0.04 ≤ x ≤ 0.26) were obtained from mixtures of VVOPO4 and WVOPO4 by conventional solid state reactions and by solution combustion synthesis. Single crystals of up to 3 mm edge length were obtained by chemical vapor transport (CVT) (800 → 700...

Along the quasi-binary section Li3PO4—Cu3PO4 three structurally different phases Li3-xCuxPO4 are prepared under equilibrium conditions using Li3PO4, Li4P2O7, LiPO3, Cu2O, Cu, and Cu3(PO4)2 as starting materials (evacuated silica tubes, 600—900 °C, 3—14 d, quenching).

A combined structural study on ternary phosphate glasses (MnO) x (NaPO 3) 1−x , x = 0.0, 0.024, 0.048, 0.167, is performed using X-ray diffraction, EXAFS and Raman spectroscopy. The mean Mn-O nearest-neighbour distance and the Mn-O coordination number in the glass with 16.7 mol% MnO are 2.15(2 A and 5.7 ± 0.4, respectively. Depolymerization of the...

NiO-doped sodium metaphosphate glasses (NaPO 3) 1−x (NiO) x (0.008 ≤ x ≤ 0.30) show a color shift from yellow to orange-brown with increasing NiO concentration. XANES and EXAFS spectra of these glasses suggest the presence of [Ni II O 6 ] groups as chromophores. EXAFS (Ni K-edge) anal-ysis of the NiO-doped phosphate glasses including an evaluation...

Several REZnPnO phases of the ZrCuSiAs type (RE = rare earth element, Pn = P, As, Sb) were synthesized in X-ray-pure form in NaCl/KCl salt fluxes. The structure of PrZnSbO was refined from single-crystal diffractometer data: P4/nmm, a = 418.79(8), c = 946.7(5) pm, wR2 = 0.0349, 192 F

The iron borate beta-FeB2O4 was synthesized under high-pressure/high-temperature conditions of 8 GPa and 1030 degrees C. The structure of beta-FeB2O4 is isotypic to HP-NiB2O4, representing the second example of a borate in which every BO4 tetrahedron shares a common edge with a second one. beta-FeB2O4 crystallizes in the space group C2/c (Z = 4) wi...

In 2 Ti 6 (PO 4 ) 6 [Si 2 O(PO 4 ) 6 ] has been obtained by heating (1100 °C) stoichiometric amounts of In 2 O 3 , SiP 2 O 7 , TiP 2 O 7 , and TiO 2 in air. Colourless crystals of the phosphate-silicophosphate suitable for a single crystal structure investigation have been grown by chemical vapour transport (1000°C → 900°C, mixture of 70 mg PtCl 2...

The title compounds were prepared by solid-state reactions and via tin and NaCl/KCl fluxes. They crystallize with the tetragonal ZrCuSiAs-type structure (P4/nmm, Z = 2), which was refined from single-crystal X-ray data of PrOsPO (a = 402.1(1), c = 824.0(1) pm, wR2 = 0.0490, 365 F ² ) and ThAgPO (a = 396.1(1), c = 877.8(1) pm, wR2 = 0.0307, 314 F ²...

Along the quasi-binary section Li3PO4 - CuI3PO4 three different phases Li3–xCuIxPO4 each with extended homogeneity range occur under equilibrium conditions (650 ≤ ; ≤ 700 °C). According to single-crystal X-ray structure analyses Phase 1 (0 < x ≤ 0.7) adopts the HT- or β-Li3PO4 structure type [Li2.6CuI0.4PO4, Pnma (no. 62), Z = 4, a = 10.4612(2) Å,...

ReVIIO2(PO4) (I) and (ReVII2O5)Si2 [Si2O(PO4)6] (II) are obtained from the reaction of Re2O7 and P4O10 in sealed silica tubes (temperature gradient 400 → 300 °C, 2 d).

In the s = 1/2 antiferromagnetic spin chain material TiPO4 the formation of a spin gap takes place in a two step process with two characteristic temperatures, T*=111 K and TSP=74 K. We observe an unusual lattice dynamics over a large temperature regime as well as evidence for an orbital instability preceding the spin-Peierls transition. We relate d...

On the basis of single-crystal x-ray diffraction we show that TiPO4 undergoes a spin-Peierls distortion below 74.5(5) K, with a dimerization of the Ti chains along the c axis. Between 74.5(5) and 111.6(3) K, TiPO4 develops an incommensurate (IC) phase with temperature-dependent q vector (σ1,0,0). Density functional calculations strongly suggest tha...

ReVIIO2(PO4) and (ReVII2O5)Sio2[Sit2O(PO4)6] were obtained from Re2O7 and P4O10 in sealed silica tubes (250 ≤  ≤ 400 °C). The crystal structures were solved and refined from X‐ray single crystal data (ReVIIO2(PO4): C2/c, Z = 24, a = 14.403(1) Å, b = 8.414(1) Å, c = 20.647(3) Å, β = 93.165(8)°, T = 123 K, 10352 ind. refl., 218 variables, 24 atoms i...

We investigated the magnetic and structural properties of the quasi-one-dimensional 3d1 quantum chain system TiPO4 (J~ 965 K) by magnetic susceptibility, heat capacity, electron spin resonance, x-ray diffraction, and nuclear magnetic resonance (NMR) measurements, and by density functional theory (DFT) calculations. TiPO4 undergoes two magnetostruct...

Based on our newly developed microwave cavity perturbation technique, the microwave conductivity of diverse vanadium(III), (IV), and (V) phosphate catalysts was measured under reaction conditions for the selective oxidation of n‐butane. The conductivity response on the gas phase was identified as a very sensitive measure for the redox kinetics, rev...

Co5V2(P2O7)4 was crystallized by chemical vapour transport using HCl as transport agent. Its crystal structure is isotypic to that of FeII 5FeIII 2(P2O7)4 and can be regarded as a member of the thortveitite structure family with corrugated layers of metal–oxygen polyhedra extending parallel to (010). Significant occupational disorder between cobalt...

Since their first recognition in mineral forming processes some 150 years ago chemical vapor transport reactions (CVTR) have attracted continuous scientific interest. Due to the pioneering work of Harald Schäfer quantitative understanding and exploitation of transport reactions for crystal growth, synthesis, investigation of high-temperature gas sp...

Crystals of (VO)Ti6(PO4)9 are prepared by solid state reaction of VOPO4 and Ti5O4(PO4)4 in a molar ratio of 3:1 (air, 1023 K, 14 d).

The new title compounds are prepared by reactions of the pure metals with “Si(NH)2” in a radio-frequency furnace at 1650 °C for 12 h.

Vanadyl(V)–titanium–orthophosphate (VVO)TiIV6(PO4)9 is formed by solid state reactions in the temperature range 525≤ϑ≤780 °C. At higher temperature decomposition into V2O5 and the hitherto unknown solid solution Ti(P1−xVx)2O7 (0≤x≤0.23; 0.30≤x≤0.43) is observed. The process of phase formation has been monitored by MAS-NMR (31P, 51V) spectroscopy. E...

Li2CuII5(PO4)4 has been obtained by various reactions starting from copper or Cu2O. Crystallization was achieved using I2 as oxidant and mineralizer. The new orthophosphate crystallizes in space group P$\bar{1}$, Z = 2, with a = 6.0502(3) angstrom, b = 9.2359(4) angstrom, c = 11.4317(5) angstrom, a = 75.584(2)degrees, beta = 80.260(2)degrees, ? = 7...

AbstractA total of 29 hitherto unknown vanadyl(IV)‐, vanadyl(V)‐, and vanadate(V) phosphates were synthesized, structurally characterized, and tested in terms of their behavior as catalysts in the selective oxidation of n‐butane to maleic anhydride. The new materials did not surpass the performance of commercially used (VIVO)2P2O7‐based catalysts,...

This comprehensive handbook covers the diverse aspects of chemical vapor transport reactions from basic research to important practical applications. The book begins with an overview of models for chemical vapor transport reactions and then proceeds to treat the specific chemical transport reactions for the elements, halides, oxides, sulfides, sele...