127795-40-8

Upstream product

• 333-20-0 potassium thioacyanate 
• 19229-76-6 iron(III) 
• 302-04-5 Thiocyanate 
• 4119-52-2 iron(II) thiocyanate 
• 2092-17-3 barium thiocyanate 
• 1701-93-5 silver thiocyanate 
• 7705-08-0 iron(III) chloride 
• 463-56-9 thiocyanic acid 
• 1111-67-7 copper(I) thiocyanate 
• 592-85-8 mercury(II) thiocyanate 
• 7439-89-6 iron(II) 
• 4119-52-2 iron(III) thiocyanate 
• 767234-62-8 iron(II) carbonate 
• 3129-90-6 isothiocyanic acid 

Downstream Products

• 61406-88-0 2-Methylcyclohexylthiocyanat 
• 61406-91-5 1,2-Dimethylcyclohexylthiocyanat 
• 463-56-9 thiocyanic acid 
• 124-38-9 carbon dioxide 
• 7664-93-9 sulfuric acid 
• 7553-56-2 iodine 
• 540-72-7 sodium thiocyanide 
• 460-19-5 ethanedinitrile 
• 74-90-8 hydrogen cyanide 
• 7783-06-4 hydrogen sulfide 
• 7664-41-7 ammonia 
• 64-19-7 acetic acid 
• 7439-89-6 iron 
• 7704-34-9 sulfur 

Relevant academic research and scientific papers

A thermal- and light-induced switchable one-dimensional rare loop-like spin crossover coordination polymer

Rare loop-like isostructural one-dimensional coordination polymer (1D-CP) systems formulated as {Fe(DPIP)2(NCSe)2}n·4DMF (1) and {Fe(DPIP)2(NCSe)2}n·4DMF (2) were obtained by self-assembling FeII and pseudohalide NCX-(X = S, Se) ions in presence of the V-shaped bidentate bridging ligand, namely, N,N′-dipyridin-4-ylisophthalamide (DPIP), and were characterized by elemental analysis, IR spectroscopy, TGA, single crystal X-ray diffraction and powder X-ray diffraction. The magnetic studies show that complex 2 undergoes a complete thermally induced spin crossover (SCO) behavior centered at T1/2 = 120 K with ca. 5 K thermal hysteresis loop and light-induced excited spin state trapping effect (LIESST) with TLIESST = 65 K. However, either the homologous X = S (1) or the desolvated form of complex 2 is high spin at all temperatures, proving further the concerted synergy for the SCO of 2 between the intrinsic ligand field and that indirectly induced via hydrogen bond interaction. The current results provide valuable information for the design of new 1D SCO systems via the rational control of the cooperated effects derived from the intramolecular coordination bond and the intermolecular supramolecular interactions.

Further Studies on the Spin Cross-over Phenomenon in Di-isothiocyanatobis(1,10-phenanthroline)iron(II)

Some inconsistencies in the results of earlier Moessbauer spectroscopic and magnetic susceptibility measurements on (phen = 1,10-phenanthroline) demanded a systematic reinvestigation of this system.We have prepared the complex by two different methods: precipitation in methanol (A) and extraction from 2 with acetone (B).The two samples (A and B) differ in crystal size and quality, which markedly influences the spin-transition behaviour.Moessbauer and magnetic susceptibility measurements down to ca. 4 K show that spin conversion is gradual in sample A but rather abrupt in sample B.This is supported by differential thermal analysis measurements.There is 'residual paramagnetism' of ca. 12percent in sample A, but none in sample B.A sharp fall in the Moessbauer resonance line width and a distinct irregularity in the quadropole splitting of the highspin state near Tc suggests that a structural change occurs as the system undergoes spin cross-over.Temperature-dependent changes in the X-ray diffraction patterns support this suggestion.

Three new iron(II) thiocyanato coordination polymers based on 4,4′Bipyridine as ligand and the influence of methanol on their structures

Reaction of iron(II) thiocyanate with 4,4-bipyridine (bipy) in methanol leads to the formation of three new solvates of different composition depending on the reaction conditions: At room temperature two new ligand-rich 1:2 (1:2 = ratio between metal and N-donor ligand) polymorphic forms [Fe(NCS) 2(bipy)2·2MeOH]n (1l) and [Fe(NCS) 2(bipy)(MeOH)2·(bipy)]n (III) are obtained, whereas solvothennal conditions leads to the formation of the new ligand-deficient 1:1 compound [{Fe(NCS)2(bipy)(MeOH)} 2]n (2). AU crystal structures were determined by X-ray single crystal structure analysis. In the crystal structure of modification II the metal atoms are coordinated by four bridging bipy ligands, which connect them into layers. The methanol molecules occupy voids in the structure. Compared to II in modification 1II the crystal structure contains of linear Fe-bipy-Fe chains, which are further connected by hydrogen bonds between coordinating MeOH and noncoordinated bipy ligands into layers. The ligand-deficient 1:1 compound 2 shows a completely different coordination topology with, linear Fe-bipy-Fe chains, which are connected by coordinating methanol molecules into double-chains. In all compounds the thiocyanato anions are terminal TV-bonded to the metal atoms. Investigation of the thermal behavior of compound II shows a two-step decomposition, in which ligand-deficient intermediates are formed. Magnetic measurements on II reveal Curie-Weiss paramagnetism with increasing antiferromagnetic interactions on cooling.

Strengthening the Magnetic Interactions in Pseudobinary First-Row Transition Metal Thiocyanates, M(NCS)2

Understanding the effect of chemical composition on the strength of magnetic interactions is key to the design of magnets with high operating temperatures. The magnetic divalent first-row transition metal (TM) thiocyanates are a class of chemically simple layered molecular frameworks. Here, we report two new members of the family, manganese(II) thiocyanate, Mn(NCS)2, and iron(II) thiocyanate, Fe(NCS)2. Using magnetic susceptibility measurements on these materials and on cobalt(II) thiocyanate and nickel(II) thiocyanate, Co(NCS)2 and Ni(NCS)2, respectively, we identify significantly stronger net antiferromagnetic interactions between the earlier TM ions-a decrease in the Weiss constant, θ, from 29 K for Ni(NCS)2 to-115 K for Mn(NCS)2-a consequence of more diffuse 3d orbitals, increased orbital overlap, and increasing numbers of unpaired t2g electrons. We elucidate the magnetic structures of these materials: Mn(NCS)2, Fe(NCS)2, and Co(NCS)2 order into the same antiferromagnetic commensurate ground state, while Ni(NCS)2 adopts a ground state structure consisting of ferromagnetically ordered layers stacked antiferromagnetically. We show that significantly stronger exchange interactions can be realized in these thiocyanate frameworks by using earlier TMs.

Two novel high-dimensional iron(ii) coordination polymers modeled by semi-rigid tetrapyridines

Two new iron(ii) coordination polymers with the formula [Fe(TPOM)(SCN) 2]·2(HN(CH3)2)·4(H2O) (1, TPOM = tetrakis(4-pyridyloxymethylene)methane) and [Fe(TPOM2)(SCN) 2]·2(CH3OH) (2, TPOM2 = tetrakis(3- pyridyloxymethylene)methane), have been synthesized and characterized by elemental analysis, IR spectroscopy, TGA, magnetic measurements and X-ray single-crystal diffraction. Compound 1 crystallizes in the orthorhombic space group Cccm, and exhibits a 3D porous pts framework in which the Fe II(NCS)2 units are linked by the tetra-topic TPOM ligands. In contrast, compound 2 crystallizes in the monoclinic space group C2/c, whose crystal structure consists of a 2D sheet formed by the connection of Fe II(NCS)2 units and tetra-topic TPOM2 ligands. Interestingly, every 2D sheet interleavingly stacks over each other to totally construct a [4] tiling structure with a plane net signature of [122] 4[4·4·4·4]. Temperature-dependent SQUID under variable external pressure and X-ray diffraction measurements indicate that the iron(ii) ions in 1 and 2 remain in the high spin state over the temperature range of 2-300 K.

Stabilization of the Low-Spin State in a Mononuclear Iron(II) Complex and High-Temperature Cooperative Spin Crossover Mediated by Hydrogen Bonding

The tetrapyridyl ligand bbpya (bbpya=N,N-bis(2,2′-bipyrid-6-yl)amine) and its mononuclear coordination compound [Fe(bbpya)(NCS)2] (1) were prepared. According to magnetic susceptibility, differential scanning calorimetry fitted to Sorai's domain model, and powder X-ray diffraction measurements, 1 is low-spin at room temperature, and it exhibits spin crossover (SCO) at an exceptionally high transition temperature of T1/2=418 K. Although the SCO of compound 1 spans a temperature range of more than 150 K, it is characterized by a wide (21 K) and dissymmetric hysteresis cycle, which suggests cooperativity. The crystal structure of the LS phase of compound 1 shows strong N-H?S intermolecular H-bonding interactions that explain, at least in part, the cooperative SCO behavior observed for complex 1. DFT and CASPT2 calculations under vacuum demonstrate that the bbpya ligand generates a stronger ligand field around the iron(II) core than its analogue bapbpy (N,N'-di(pyrid-2-yl)-2,2′-bipyridine-6,6′-diamine); this stabilizes the LS state and destabilizes the HS state in 1 compared with [Fe(bapbpy)(NCS)2] (2). Periodic DFT calculations suggest that crystal-packing effects are significant for compound 2, in which they destabilize the HS state by about 1500 cm-1. The much lower transition temperature found for the SCO of 2 compared to 1 appears to be due to the combined effects of the different ligand field strengths and crystal packing.

Effect of metal dilution on the thermal spin transition of [Fe xZn1-x (bapbpy)(NCS)2]

This study reports on the effects of zinc dilution on the structure and magnetic properties of the mononuclear two-step spin-crossover compound [Fe(bapbpy)(NCS)2] (1; bapbpy = N6,N6′-di(pyridin-2-yl)-2, 2′-bipyridine-6,6′-diamine). The zinc analogue of 1, [Zn(bapbpy)(NCS)2] (3), was synthesized and characterized by X-ray powder diffraction, which suggests different structural features from 1. The crystal structure of the related compound [Fe(bapbpy)(NCS)]2[Zn- (NCS)4]·3DMF (4) was determined by single-crystal X-ray diffraction. Unlike the hexacoordinate FeII in 1, the ZnII ions in 4 are pentacoordinate. Nine diluted powder samples [FexZn1-x (bapbpy)(NCS) 2] were prepared with iron fractions of x = 0.89, 0.81, 0.76, 0.65, 0.60, 0.53, 0.44, 0.38, and 0.24. According to powder X-ray diffraction and infrared spectroscopy, the phase of compound 1 is retained in the zincdiluted samples when x > 0.53. At higher dilutions (i.e., when x a single-step SCO material at x = 0.76. Upon additional increase of the zinc contents, the cooperativity of the SCO gradually vanishes to lead to a noncooperative SCO material at the lowest iron fraction studied (x = 0.24). Despite the different coordination properties of the bapbpy ligand towards FeII and ZnII, the spin crossover of the hexacoordinate FeII complex is robust enough to withstand dilution into a magnetically silent ZnII phase that is structurally different from that of the iron compound.

Nanoporosity, Inclusion Chemistry, and Spin Crossover in Orthogonally Interlocked Two-Dimensional Metal-Organic Frameworks

[Fe(tvp)2(NCS)2] (1) (tvp=trans-(4,4′-vinylenedipyridine)) consists of two independent perpendicular stacks of mutually interpenetrated two-dimensional grids. This uncommon supramolecular conformation defines square-sectional nanochannels (diagonal≈2.2 nm) in which inclusion molecules are located. The guest-loaded framework 1@guest displays complete thermal spin-crossover (SCO) behavior with the characteristic temperature T1/2 dependent on the guest molecule, whereas the guest-free species 1 is paramagnetic whatever the temperature. For the benzene-guest derivatives, the characteristic SCO temperature T1/2 decreases as the Hammet σp parameter increases. In general, the 1@guest series shows large entropy variations associated with the SCO and conformational changes of the interpenetrated grids that leads to a crystallographic-phase transition when the guest is benzonitrile or acetonitrile/H2O.

Highly Ordered, Self-Assembled Monolayers of a Spin-Crossover Complex with In-Plane Interactions

For the technological integration of molecular switches in electronic devices, self-assembling nanomaterials of such switches are highly sought after. The syntheses of a new tetrapyridyl ligand bearing a C12 alkyl chain and two N?H bridges (compound 1) and of its iron(II) complex [Fe(1)(NCS)2] (compound 2), are described. Magnetic susceptibility data for bulk samples of 2 confirmed their gradual spin-crossover properties. The self-assembly of 1 and 2 on highly ordered pyrolytic graphite surfaces (HOPG) was investigated by Scanning Tunneling Microscopy (STM). Both compounds 1 and 2 formed ordered monolayers after deposition by drop casting. The patterns of the two compounds are very different, which is attributed to the fundamentally different hydrogen bonding networks before and after coordination of Fe(NCS)2 to the tetradentate chelate. Two possible models for the self-assembly of 1 and 2 are provided. This work suggests that it is possible to design molecular switches that self-assemble on surfaces in highly ordered monolayer films. This is a significant step in the development of spin-switching materials, which may streamline the integration of molecular switches in for example memory and sensing devices.

New thiocyanato iron(II) complex with 3,5-bis(3-pyridyl)-1,2,4-thiadiazole: Synthesis, structure, magnetic and spectral properties

The new iron(II) complex [Fe(NCS)2(CH3OH) 2(bpta)2] (bpta = 3,5-bis(3-pyridyl)-1,2,4-thiadiazole) has been prepared by refluxing Fe(NCS)3 or Fe(NCS)2 with thionicotinamide in methanol solution. It is supposed that the bpta ligand is generated in situ by the oxidative dimerization of thionicotinamide. The complex was characterized by X-ray structural analysis at 150 and 293 K, elemental analysis, spectral and magnetic measurements. The compound crystallizes in the monoclinic P21 space group, with unit cell parameters at 293 K: a = 7.869(2), b = 17.056(3), c = 12.637(3) ?, β = 102.88(1). The crystal structure analysis showed that the iron atom has a distorted octahedral environment with FeN4O2 chromophore. Iron atom is coordinated by two nitrogen atoms from NCS- ions, by two oxygen atoms from methanol molecules in the equatorial plane and by two nitrogen atoms of pyridine rings from dpta ligands in axial positions. The crystal lattice forms 2D supramolecular network which is stabilized by a system of hydrogen bonds and π-π stacking interactions. Variable-temperature magnetic susceptibility data in the temperature range 1.8-300 K show that the octahedral iron(II) is high-spin S = 2(5T2g) and as a result effects due to zero-field splitting are anticipated at low temperatures. Structural parameters and infrared spectra of similar complexes are compared and discussed.