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The synthesis, crystal structures and properties of two alkali metal 3-nitrohydrogenphthalates obtained by a 1:2 reaction of M2CO3 (M = K or Na) with 3-nitrophthalic acid (LH2) are reported. In the anhydrous potassium coordination polymer [K(LH)] (LH = 2-carboxy-3-nitrobenzoate) 1, the K+ cation is bonded to nine oxygen atoms from six symmetry related (LH)– ligands resulting in a distorted {KO9} coordination polyhedron. Five of the six oxygen atoms including a nitro oxygen atom of the crystallographically unique 2-carboxy-3-nitrobenzoate are involved in metal binding. The μ6-bridging mode of (LH)– places the K+ cations into the layers of the two-dimensional (2D) coordination polymer. Each {KO9} polyhedron in 1 shares edges with two other polyhedra along the b and c axes. A low temperature structure redetermination of [Na(L#H)(H2O)3]·H2O (L#H = 2-carboxy-6-nitrobenzoate) 2 has revealed that the (L#H)− anion is bonded to the Na+ cation in a monodentate fashion via the carbonyl oxygen atom of the –COOH group and two of the three unique aqua ligands exhibit a bridging bidentate mode stabilizing a chain polymer. The structure of compound 2 thus consists of chains of edge-sharing {NaO6} octahedra. Thermal decomposition of 1 or 2 results in the formation of metal carbonate residues.

Hydrothermal synthesis, crystal structure and properties of a new heterometallic coordination polymer [(VO(terpy))4(MoO4)2(Mo8O26)]·2H2O (1) (terpy = 2,2′;6′,2″-terpyridine) are reported. Compound 1 contains two crystallographically unique vanadium(IV) atoms, bonded to a terminal oxido ligand and further coordinated to a terpy ligand. The three N atoms of terpy occupy the meridional sites of a distorted {VN3O3} octahedron. A γ-octamolybdate (Mo8O26)4– located on an inversion centre and a tetraoxidomolybdate (MoO4)2– function as bridging ligands. The μ3-bridging tridentate binding of (MoO4)2– leads to the formation of a {V4Mo2O12}4+ cationic unit consisting of an eight-membered heterometallic {Mo2V2O4} ring with protruding oxidovanadium handles. A pair of {V4Mo2O12}4+ units are bridged by the centrosymmetric (Mo8O26)4– ligand, resulting in the formation of an infinite chain of alternating {V4Mo2O12}4+ cations and (Mo8O26)4– anions.

The reaction of Na2MoO4·2H2O with 2-amino-2-(hydroxymethyl)propane-1,3-diol (LH) in water at room temperature results in the formation of the heterometallic coordination polymer [Mo2O6L2(Na2(H2O)4)]·2H2O 1 (L = 2-amino-3-hydroxy-2-(hydroxymethyl)propan-1-olato). The structure of 1 consists of a neutral (Mo2O6) unit located on an inversion center. The Mo atoms exhibit hexa-coordination and are bonded to two terminal and two bridging oxido ligands, an alkoxide oxygen and the amine N atoms of an anionic ligand L– resulting in the formation of an edge-sharing {Mo2O8N2} bioctahedron. The Na+ cations of a centrosymmetric bis(μ2-aqua)-bridged (Na2(H2O)4)2+ unit are penta-coordinated and bonded to two symmetry related L– ligands via the oxygen atoms of their OH groups. The µ3-bridging tetradentate binding mode of L– results in the formation of a two-dimensional heterometallic coordination polymer. The constituents of 1 viz. (Mo2O6), (L)–, (Na2(H2O)4)2+ and lattice water molecules are interlinked with the aid of three varieties of hydrogen bonding interactions. The corresponding tungstate reported recently has been obtained through a similar synthetic protocol and is isostructural.

The reaction of the water-rich compound [Sr(H2O)7(4-nba)](4-nba)·2H2O (4-nba = 4-nitrobenzoate) with dimethylformamide (DMF) or N-methylformamide (NMF) or pyrazole (Pyr) resulted in the incorporation of the O- or N-donor ligand in the coordination sphere of Sr(II) forming the one-dimensional (1D) coordination polymers [Sr(H2O)3(DMF)(4-nba)](4-nba) (1), [Sr2(H2O)2(NMF)3(4-nba)4] (2) and [Sr(Pyr)2(4-nba)2] (3) respectively. In the case of Mg(II), a similar protocol afforded crystallization of [Mg(H2O)6](4-nba)2(DMF)2 (4), [Mg(H2O)6](3-nba)2(Acet)2 (5), (3-nba = 3-nitrobenzoate; Acet = Acetamide) in which the amides function as solvates. The syntheses, crystal structures and properties of 1–5 are reported. In 1–3 Sr(II) exhibits eight coordination while Mg(II) displays hexa coordination in 4 and 5 forming the centrosymmetric octahedral [Mg(H2O)6]2+ unit. The µ3-η2:η2-tetradentate bridging binding modes in 1 and 2 and µ2-η1:η2-tridentate bridging binding mode in 3 of the 4-nitrobenzoate result in the formation of 1D coordination polymer. The carboxylate ion does not coordinate to Mg(II) in 4 and 5, but functions as a charge balancing counter anion. The {SrO8} polyhedra in 1 and {SrN2O6} polyhedra in 3 share edges in the 1D chains, while in 2 the {SrO8} polyhedra are linked into a 1D chain via alternate edge and face sharing arrangement. Compounds 1 (C–H···O, O–H···O) and 3 (C–H···O, N–H···O) exhibit two varieties of hydrogen bonding interactions while 2 and 5 are involved in three types of H-bonding interactions viz. C–H···O, O–H···O, N–H···O. A study of the structural features of several alkaline-earth 4-nitrobenzoates is described.

An attempted isolation of the elusive diammonium tetraoxidotungstate (NH4)2[WO4] as its imidazole (Im) adduct resulted in the serendipitous formation of hepta(ammonium) penta(1H-imidazol-3-ium) par...

The authors of the title paper (Journal of Optics 49:181–186, 2020) claim to have grown a so-called urea potassium dichromate (UPDC) by slow evaporation of an aqueous solution containing equimolar amounts of urea and potassium dichromate and characterized it based on a unit cell study. A critical analysis reveals that the claims in the title paper are erroneous. Hence, we reinvestigated the crystal growth reaction and determined the structure of the product crystal. Based on these studies, we prove that due to no chemical reaction between the reagents fractional crystallization of potassium dichromate (K2Cr2O7) occurs and not formation of any so-called UPDC crystal. Taking the title crystal as an example we show the importance of reporting single-crystal structure for new compound characterization.

The authors of the title paper [J. Mater. Sci. Mater. Electron. 31, 13310–13320 (2020)] report to have grown a so-called l-asparagine thioacetamide (LATA) single crystal by slow evaporation of an aqueous solution containing l-asparagine monohydrate and thioacetamide in 1:1 ratio. The same research group has claimed in another paper [J. Mater. Sci. Mater. Electron. 31, 791–798 (2020)] to have grown a so-called NLO-active potassium hydrogen phthalate fumaric acid crystal (KHPF). In this comment we prove that LATA and KHPF are improperly characterized crystals and both papers are erroneous.

Distorted octahedral ruthenium(II) bis-phenanthroline compounds of the type cis-[Ru(phen)2(L)2](PF6)2 (L = isoquinoline 1; phthalazine 2) were synthesized and their photochemistry was investigated. The photodissociation of the monodentate N-heterocyclic co-ligands upon blue light irradiation (λirr = 470 nm) occurs much more readily in 1 than in 2 with the first ligand dissociating faster than the second ligand. The density functional theory (DFT) calculations were performed to investigate geometries of the 3MLCT, 3TS, and dissociative 3MC states and the triplet potential energy surfaces. DFT and time-dependent DFT (TD-DFT) calculations reveal a smaller 3MLCT-3MC energy gap for 1 (0.025 eV) than in 2 (0.090 eV) suggesting the faster dissociation of the first co-ligand in both 1 and 2. On the other hand, the 3MLCT-3MC energy gap is moderately larger for the monochloro-substituted photoproducts 1a (0.389 eV) and 2a (0.396 eV), leading to the conclusion that the second co-ligand dissociation is slower in both 1a and 2a. This is also in agreement with the observed values of quantum yields. Molecular orbital analysis along the triplet potential energy surface scan for Ru–N(co-ligand) bond stretching suggests that the lower energy singly occupied molecular orbital (SOMO1) of 3MLCT, comprised of a dπ orbital of Ru with little contribution of π orbital of the co-ligand, does not change much when Ru–N bond stretches to reach 3MC. The higher-energy SOMO2 of the 3MLCT state is mostly phenanthroline based π* orbital. Upon stretching the Ru–N distance, the π* orbital of phenanthroline in the 3MLCT state and dσ* orbital of the dissociative 3MC state are seen to be mixing in an antibonding fashion especially after transition state (3TS). This mixing of the dσ* orbital with the π* orbital is one of the important factors favoring the release of the N-heterocyclic co-ligand to give photodissociation products.

The synthesis, spectral characteristics, thermal properties and single crystal structures of [Co(N-meim)2(4-nba)2] (N-meim = N-methylimidazole; 4-nba = 4-nitrobenzoate) (1), [Co(2-meim)2(4-nba)2] (2-meim = 2-methylimidazole) (2), [Co(pyr)3(4-nba)2] (pyr = pyrazole) (3), [Co(H2O)2(form)2(4-nba)2]·form (form = formamide) (4), [Co(H2O) (aceta)2(4-nba)2] (aceta = acetamide) (5) and [Co(H2O)3(N-mepyr)(4-nba)](4-nba) (N-mepyr = N-methylpyrazole) (6) are reported. The central Co(II) exhibits tetrahedral geometry in 1 and 2, trigonal bipyramidal geometry in 3 and octahedral geometry in 4–6. In the anhydrous compounds 1–3 as well as the diaqua compound 4, the monoaqua compound 5 and the triaqua compound 6, the neutral N-donor co-ligands or the O-donor amides function as terminal ligands. The aromatic 4-nba ligand exhibits monodentate binding mode in 1–4 and monodentate and bidentate binding in 5, while 6 contains an uncoordinated 4-nba in addition to a bidentate 4-nba ligand. A single C-H···O interaction links molecules of 1 into an infinite chain while the N-H···O bonds in 2 result in a two-dimensional network. Compounds 4 and 5 exhibit three varieties of H-bonding. Thermal decomposition of 1–6 results in the formation of a spinel oxide. A comparative study of thirty-one structurally characterized cobalt-4-nitrobenzoates is described.

The synthesis, spectra, electrochemical studies, single crystal structures and DFT studies of two new mixed ligand copper(II) malonates viz. [Cu(H2O)(bpy(OH)2)(mal)]·H2O 1 and [Cu(H2O)(dmp)(mal)]·2H2O 2 (bpy(OH)2) = 2,2′-bipyridine-6,6′-diol; dmp = 6,6′-dimethyl-1,10-phenanthroline; H2mal = malonic acid) are reported. The malonate, bpy(OH)2 (in 1), dmp (in 2) function as bidentate ligands in the distorted square pyramidal Cu(II) compounds while the aqua ligand occupies the axial site in 1. In contrast, one N of dmp occupies the axial site in 2. ESR studies reveal the distorted coordination geometry of Cu(II) in 1 and 2. Extensive hydrogen bonding (O−H⋅⋅⋅O and C−H⋅⋅⋅O) is observed between the malonate oxygens, oxygens of water and the monomeric Cu(II) species resulting in the formation of hydrogen bonded network structure in 1 and 2. The neutral monomeric Cu(II) species and lattice water molecules in 2 are linked via O−H⋅⋅⋅O hydrogen bond forming a water dimer. Both compounds exhibit π⋅⋅⋅π stacking and carbonyl(lp)⋅⋅⋅π interactions (in 2) stabilize the structure. DFT studies reveal stronger hydrogen bond energy for 2 compared to 1, while π⋅⋅⋅π stacking energy is larger in 1 than in 2 and carbonyl(lp)⋅⋅⋅π interactions in 2 are found to be moderate. In a series of five coordinated mixed ligand Cu(II) malonates, compound 2 exhibits maximum deviation of the {CuN2O3} polyhedron from square pyramidal towards trigonal bipyramidal geometry. The supramolecular network structures of [Cu(H2O)(bpy(OH)2)(mal)]·H2O 1 and [Cu(H2O)(dmp)(mal)]·2H2O 2 are directed by O–H⋅⋅⋅O and C–H⋅⋅⋅O interactions. Additionally π⋅⋅⋅π stacking in 1 and π⋅⋅⋅π /carbonyl(lp)⋅⋅⋅π interactions in 2 contribute to the structure stabilization. 2 is an unique example showing severe distortion of the {CuN2O3} polyhedron.

The authors of the published title paper (Bull. Mater. Sci. 2020 43 17) claim to have grown a resorcinol-doped potassium hydrogen phthalate (RKHP) crystal by a slow evaporation method. It was reported that the organic dopant enhances the second harmonic generation efficiency (SHG) of potassium hydrogen phthalate (KHP). In this letter to Editor, many points of criticism concerning the crystal growth and the characterization of the so-called RKHP crystal are discussed to prove that the published original paper is erroneous.

The authors of the title paper (Chin J Phys 63 (2020) 70–77) claim to have grown a Zn2+ ion influenced ammonium dihydrogen phosphate (Zn-ADP) crystal by the slow solvent evaporation technique. In this comment, many points of criticism, concerning the crystal growth and characterization of the so-called Zn-ADP crystal are discussed to prove that it is a dubious material and the title paper is erroneous.

The synthesis, spectral characterization, crystal structure and properties of [Ba(H2O)2(NMF)2(4-nba)2], 1 (NMF = N-methylformamide; 4-nba = 4-nitrobenzoate), are reported. 1H and 13C NMR spectral d...

In an earlier published paper, Srineevasan and Rajasekaran (J. Mol. Struc. 1048, (2013) 238–243) [1] reported to have grown a so called 2-aminopyridine bis thiourea zinc sulphate single crystal (1) by slow evaporation technique at room temperature. A reinvestigation of the reported crystal growth reaction reveals that addition of 2-aminopyridine into an aqueous solution containing zinc sulphate heptahydrate and thiourea in 1:2 mol ratio initially results in the formation of a white precipitate. Filtration of the precipitate followed by slow evaporation of the filtrate results in the crystallization of the known compound sulphatotris(thiourea)zinc(II) (2) and NOT any 2-aminopyridine bis thiourea zinc sulphate.

The syntheses and crystal structures of three anionic water rich phthalates charge balanced by piperazinediium (pipH2)2+ viz. (pipH2)[M(H2O)4(pht)2]·8H2O [M = Ni (1), Co (2) and Cu(3)] (pht = phthalate) are reported. Reaction of 1–3 with imidazole (im) results in the formation of [M(im)6](pht)·H2O [M = Ni (4) and Co (5)] and [Cu2(H2O)(im)4(pht)2]·H2O (6) respectively. Compounds 1–6 have been characterised by spectral, thermal, electrochemical and magnetic studies and their structures determined. The phthalate ligand displays a monodentate binding mode in the bis(phthalato) compounds 1–3. The centroid to centroid distance (Cg⋯Cg) between the adjacent phthalate rings in 1–3 is ∼4.0 A. In the hexaimidazole compounds 4 and 5 phthalate functions as a charge balancing dianion. The H-bonding interactions among lattice water molecules lead to the formation of a water dodecamer cluster in 1–3 with R6 water motif which further extends into a staircase pattern with T4(2)6(2) extended motif. The intra- and intermolecular H-bonding via C H⋯O, N H⋯O, O H⋯N and O H⋯O interactions results in an intricate supramolecular architecture. Thermal studies of 1–3 reveal interesting dehydration and rehydration characteristics. Compounds 1 and 2 undergo crystalline-amorphous-crystalline transformation during de- and rehydration.

The authors of the title paper (Appl Phys A 126:394, 2020) report to have grown a new nonlinear optical potassium hydrogen oxalate (KHO) single crystal, which exhibits second harmonic generation response. In this comment, it is shown that these claims are erroneous since KHO is a well-known solid which crystallizes in the centrosymmetric P21/c space group.

The asymmetric unit of the title barium coordination polymer, [Ba(C6H2N3O7)2(C2H6OS)] n , consists of a barium cation (site symmetry m) and a dimethyl sulfoxide (DMSO) ligand (point group symmetry m) and a 2,4,6-trinitrophenolate anion located in general positions. The S atom and the methyl group of DMSO are disordered over two sets of sites. The DMSO ligand bridges a pair of BaII atoms resulting in a chain extending parallel to the a axis. The unique 2,4,6-trinitrophenolate anion also bridges a pair of BaII ions via the phenolic oxygen atom, with each BaII being additionally bonded to an oxygen atom of an adjacent nitro group. The μ 2-monoatomic bridging binding mode of both types of ligands results in the formation of an infinite chain of face-sharing {BaO10} polyhedra flanked by the remaining parts of the 2,4,6-trinitrophenolato and DMSO ligands. In the one-dimensional coordination polymer, parallel chains are interlinked with the aid of C—H...O hydrogen bonds.

The title compound, [Co2(C7H4NO4)2(C10H8N2)2(H2O)4](C7H4NO4)2, consists of a centrosymmetric bimetallic complex charge-balanced by free 4-nitrobenzoate anions. The CoII ion exhibits a distorted cis-CoN2O4 octahedral coordination environment and the Co...Co separation is 3.326 (2) Å. In the crystal, the dications and anions are linked by O—H...O and C—H...O hydrogen bonds.

The asymmetric unit of the binuclear title compound, [Cu2(C8H7O3)4(H2O)2], comprises two halves of diaquatetrakis(μ-3-methoxybenzoato-κ2 O 1:O 1′)dicopper(II) units. The paddle-wheel structure of each complex is completed by application of inversion symmetry, with the inversion centre situated at the midpoint between two CuII atoms in each dimer. The two CuII atoms of each centrosymmetric dimer are bridged by four 3-methoxybenzoate anions resulting in Cu...Cu separations of 2.5961 (11) and 2.6060 (12) Å, respectively. The square-pyramidal coordination sphere of each CuII atom is completed by an apical water molecule. Intermolecular O—H...O hydrogen bonds of weak nature link the complexes into layers parallel to (100). The three-dimensional network structure is accomplished by C—H...O hydrogen bonds interlinking adjacent layers.

The structure of the title salt, C6H10N2 2+·2C7H7O3S−, consists of a unique benzene-1,2-diaminium dication charge balanced by a pair of crystallographically independent 4-methylbenzene-1-sulfonate anions. The cations and anions are interlinked by several N—H...O hydrogen bonds.

The authors of the title paper (Colloids and Surfaces A 606 (2020) 125456) reported to have hydrothermally synthesized nanosheet-constructed porous MnMoS4 arrays on 3D Ni foam as a binder-free electrode in high performance supercapacitors. A critical analysis of the reported results viz. X-ray powder pattern and the elemental composition reveals that the electrode material is not MnMoS4 as it contains substantial oxygen in addition to less Mo content than Mn. In this letter to the Editor, many points of criticism concerning the hydrothermal synthesis and interpretation of the experimental data are described to prove that MnMoS4 (I) is a dubious material.

The authors of the title paper (J Photochem & Photobio A:Chem 393 (2020) 112413) claim to have synthesized a toluidine tartrate (TT) crystal and examined its nonlinear optical (NLO) behavior by experimental and theoretical studies. In this critique, it is shown that the so-called TT crystal is a surface degraded material and the experimental and theoretical data contradict literature reports on the 1:1 salt of p-toluidine and l -tartaric acid.

In this short review, a critical analysis of the purported ferroelectric and piezoelectric properties of crystals which have been published is critiqued.

It is shown that three papers published recently by Allen Moses et al. on “L-threoninium phosphate”, “L-threoninium sodium fluoride” and “L-threoninium tartrate” are completely erroneous. In fact, only crystals of L-threonine were obtained in all cases.

In this study we examine a case of iron doping in sodium para-nitrophenolate dihydrate single crystal recently reported by Dalal and Kumar (Mater. Lett. 165 (2016) 99–102). We show that, addition of ferric (Fe3+) ions into an aqueous solution of sodium para-nitrophenolate dihydrate (1) results in immediate precipitation of an insoluble brown hydrous iron(III) oxide, which precludes any doping (incorporation) of iron in (1). The crystals grown after filtering the precipitate show a negative spot test for iron and exhibit sharp proton resonances in the 1H NMR spectrum proving no incorporation of iron in (1). In addition to highlighting the importance of the reactive chemistry of the dopant and the host for crystal growth from solution, we show that ferric ions cannot be doped into a host material whose aqueous solution is alkaline.

In a recent paper Azhar et al., (Mater. Res. Innov. https://doi.org/10.1080/14328917.2017.1392694) claim to have grown a tris (thiourea) potassium barium sulphate (TTPBS) crystal, which acc...

We show that a recently published paper “Spectroscopic evaluation of Alanine Adipate nonlinear optical materials growth dynamics: Mechanical and thermal optimization” (S. Akilandeswari, L. Jothi, J. Mol. Struct. 1240 (2021) 130577) is completely erroneous. A so-called “alanine adipate” actually is adipic acid, which is centrosymmetric and therefore cannot be a nonlinear optical crystal showing second harmonic activity.

The authors of the title paper (Optics and Laser Technology 83 (2016) 49–54) claim to have grown a ‘lithium sulphate doped l -threonine’ crystal by slow evaporation of an aqueous solution containing equimolar amounts of l- threonine and lithium sulphate. A reinvestigation of the crystal growth reaction reveals that fractional crystallization of l -threonine occurs. In this letter to the Editor, we prove that the so-called lithium sulphate doped l -threonine is a dubious crystal and not a ferromagnetic material

The authors of the title paper (Mater. Chem. Phy. 205 (2018) 138–146) claimed to have grown for the first time a new alkali metal borate with formula Na6[B4O5(OH)4]3·8H2O (I) by slow evaporation of an aqueous solution containing NaOH, H3BO3 and C3H4O4 in 3:1:1 mol ratio. In this letter to the Editor, many points of criticism concerning the crystal growth, structure characterization and interpretation of the spectral and thermal data of I are described to prove that it is improperly characterized.

The authors of the title paper (J.Mol. Struc. 1207 (2020) 127750) claim to have grown a novel organic nonlinear optical (NLO) toluidine tartrate (TT) single crystal. In this letter to the Editor, we prove that the so-called TT crystal is not a novel NLO material but is in fact, the well-known colorless 1:1 salt of p-toluidine and l -tartaric acid. The title crystal's brown color is due to extensive surface degradation.

The authors of the title paper (Optics and Laser Technology 107 (2018) 478–483) report to have grown a so-called ‘ l- Lysine doped oxalic acid’ crystal by slow evaporation of an aqueous solution containing l- lysine and oxalic acid in 1:2 mol ratio. In this letter to the Editor, we prove that the ‘ l- lysine doped oxalic acid’ is a dubious crystal.

The authors of the title paper (Opt. Laser Technol. 137 (2021) 106800) claim to have performed an experimental and computational study of anilinium l -tartrate (ALT) crystal. In this letter to Editor, it is shown that the ALT crystal is a surface degraded material. A critical analysis of the title paper is presented to show that the reported experimental data contradict earlier reports on the 1:1 salts of aniline and l -tartaric acid.

The authors of the title paper (Mater. Lett. 188 (2017) 156–158) claimed to have grown potassium sodium hydroxide borate hydrate (KSB) single crystal and reported its mechanical properties in a subsequent paper (Mater. Lett. 215 (2018) 165–168). In this letter, many points of criticism concerning the crystal growth, structure characterization and interpretation of the spectral and thermal data of the so-called KSB crystal are described to prove that it is a dubious material.

The authors of the title paper (Mater. Res. Express 6 (2019) 116213) claim to have grown a nickel boro phthalate (NBP) crystal by the slow evaporation method. A critical analysis of the paper reveals that the so-called NBP is an improperly characterized material. A reinvestigation of the crystal growth reaction has been performed to unambiguously characterize the product. In this letter to the Editor, it is proved that nickel boro phthalate neither contains nickel nor phthalate but is, in fact, boric acid.

Crystals of bis(4-aminopyridinium) dichromate (C5H7N2)2[Cr2O7] (1) were isolated via slow solvent evaporation and characterized by energy dispersive spectroscopy (EDS), infrared (IR) and ultratviolet-visible (UV-Vis) spectroscopy, and single crystal X-ray diffraction. The room-temperature (RT; 298 K) phase of 1 crystallizes in the monoclinic space group P21/m. Its asymmetric unit consists of two crystallographically independent 4-aminopyridinium cations (A and B) and two halves of symmetry-independent dichromate anions (A and B). Cations and anions are linked with the aid of several moderate N–H⋯O hydrogen bonds and weak C–H⋯O interactions resulting in a three-dimensional supramolecular network. The crystal structure is further stabilized by extensive π–π stacking interactions between adjacent pyridine rings. A comparison of the structure of the RT phase of 1 and that of the low temperature (LT; 150 K) phase is described.

Dalton transactions 48(4), 1184 - 1201 (2019). doi:10.1039/C8DT04205E, Herein we present an in-depth study of precursor derived tungsten sulfides, with a focus on their micro- and local structures. We prepared a new tetrathiotungstate based precursor (N$_2$H$_5$)$_2$WS$_4$ and unveiled the details of its unique decomposition mechanism by a combination of in situ and ex situ analytical techniques. Upon heating the precursor, a new compound with composition (NH$_4$)(N$_2$H$_5$)WS$_4$ is formed by the decomposition of one hydrazinium molecule. Above ∼190 °C, (NH$_4$)$_2$WS$_4$ crystallized as the second crystalline intermediate followed by successive decomposition to WS$_2$ via amorphous WS$_3$ upon increasing the temperature. Using X-ray diffraction, total scattering data and pair distribution function (PDF) analyses we are able to develop a detailed picture of the microstructure of nanosized WS$_2$ samples obtained by the thermal decomposition of the precursor. The microstructure is described by global optimization of the stacking pattern of WS$_2$ slabs in a supercell containing a large number of layers. The results clearly demonstrate that both stacking faults and random shifts of the WS$_2$ layers contribute to the disorder in the material. This is significantly distinct to bulk materials, where solely stacking faults with no turbostratic disorder components were found.