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Luminescent ionic liquids, based on anionic Pt(ii) complexes, were developed. Depending on the cyclometalating ligands used, they exhibit thermochromic luminescence with different colours. The chromic properties in the flexible liquid and glass states emerge through the self-assembling character of the square-planar Pt(ii) complexes. [ABSTRACT FROM AUTHOR]

Double-decker platinum complexes with N -heteroaromatic ligands have attracted increasing interest due to their outstanding luminescent properties and rich redox behavior. In this review, the design principles and recent observations on luminescent and redox-active double-decker platinum complexes are discussed. Because these properties are precisely controlled by intra- and intermolecular Pt⋯Pt electronic interactions, double-decker platinum complexes have been also used to obtain phenomena driven by stimulus–responsive color and luminescence change, such as vapochromism, mechanochromism, thermochromism, and electrochromism. This review also summarizes chromic materials based on double-decker platinum complexes influenced by changes in the Pt⋯Pt electronic interactions. [ABSTRACT FROM AUTHOR]

An ionic liquid fabricated from an anionic cyclometalated platinum(ii) complex and an imidazolium cation exhibits dual emission from the monomeric and aggregated forms of the platinum complex anions, leading to temperature-dependent color changes of luminescence. [ABSTRACT FROM AUTHOR]

The title dinuclear platinum(III) complex, [Pt2(C11H2N)2(C5H4NS)4], forms two crystal structures, viz. the non-solvated and acetonitrile-solvated (C2H3N) forms. For both forms, two (2-pyridylphenyl)platinum units are bridged by two pyridine-2-thiolate (pyt) anions in a head-to-tail configuration, and the other two pyridine-2-thiolate anions occupy the axial position, coordinated through their S atoms. The most remarkable difference between the two forms is the orientation of the axial monodentate ligands. Those for the solvated form are located over the 2-pyridylphenyl ligands, being related by a twofold axis which lies through the centre of the Pt—Pt bond, while the axial pyt ligands for the non-solvated form are oriented irregularly, which is attributable to the dimeric arrangement in the crystal. [ABSTRACT FROM AUTHOR]

Vapochromic behavior of the crystal of dicyano(2,2′-bipyridine)platinum(II), [Pt(CN) 2 (bpy)], has been investigated structurally and emission spectroscopically. Red Form with an infinite Pt···Pt chain transforms to Yellow Form reversibly by taking up water vapor. The crystal structure of Yellow Form ([Pt(CN) 2 (bpy)]·H 2 O) was determined by X-ray analysis: the square-planar complexes form the inclined stack with short and long Pt···Pt distances (3.3279(3) and 4.6814(3) Å). The crystal water makes hydrogen bonds with CN - ligands connecting the stacks. The transformation is accompanied by the sensitive luminescence change as well as the color change, which reflects the change of the Pt⋯Pt electronic interactions. The sensitive vapochromism for this system is attributable to the slight deformation of the stacking structure induced by water molecules. platinum complex luminescence spectrum vapochromism metal-metal interaction crystal structure [ABSTRACT FROM AUTHOR]

Studies the temperature dependence of both emission spectrum and crystal structure of a liner-chain platinum complex. Correlation of the luminescence emission spectrum and the Pt---Pt distance for the platinum(II) complex; Behavior the platinum complex crystal; Pi-pi interactions of the complex.

Reports on the preparation of three platinum(II) complexes and their x-ray crystal structures and luminescence properties. Synthesis; Solution and refinement of structures; Physical measurements; Structural description; Emission and absorption properties.

A hybrid vapoluminescent system exhibiting fast and repeatable response was constructed using periodic mesoporous organosilica with bipyridine moieties (BPy-PMO) and a Pt(II) complex bearing a potentially luminescent 2-phenylpyridinato (ppy) ligand. An intense red luminescence appeared when the Pt(II)-complex immobilised BPy-PMO was exposed to methanol vapour and disappeared on exposure to pyridine vapour. The ON-OFF vapochromic behaviour occurred repeatedly in a methanol/pyridine/heating cycle. Interestingly, a rapid response was achieved in the second cycle and cycles thereafter. Scanning and transmission electron microscopies (SEM/TEM), absorption and emission, and nuclear magnetic resonance spectroscopies, mass spectrometry, and powder X-ray diffraction indicated that methanol vapour induced Si-C cleavage and thus liberated [Pt(ppy)(bpy)]Cl (bpy = 2,2′-bipyridine) from the BPy-PMO framework. Furthermore, the self-assembling properties of the Pt(II) complex resulted in the formation of highly luminescent micro/nanocrystals that were homogeneously dispersed on the porous support. The unique vapoluminescence triggered by the unprecedented protodesilylation on exposure to protic solvent vapour at room temperature is attributable to BPy-PMO being a giant ligand and an effective vapour condenser. Consequently, this hybrid system presents a new strategy for developing sensors using bulk powdery materials. [ABSTRACT FROM AUTHOR]

A novel Pt(II)–diimine complex exhibits an interesting vapochromic shape‐memory behavior. The amorphous form is converted to a red luminescent vapor‐adsorbed form in the presence of alcoholic vapors. The vapor‐adsorbed form can release the vapors without collapse of the porous structure; this enables it to adsorb other vapors. The vapor‐free porous form can easily be converted to the initial amorphous form by manual grinding. These transformations enable the design of a new chemical sensor with vapor history and ON–OFF switching functions. More information can be found in the Full Paper by A. Kobayashi, M. Kato et al. on page 2682 ff. [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigated the vapochromism and hydrogen-ion concentration-dependent coloration of Dicyano(4',4'-dicarboxy-2',2'-bipyridine)platinum(II). The chemical complex used in this study exhibits a hydrogen-ion concentration-dependent multicolored polymorphism and vapochromic behavior upon exposure to certain volatile organic compounds.

A cyclometalated dinuclear platinum(II) complex bridged with pyridine-2-thiolate ions, [Pt2(ppy)2(pyt)2] (Hppy = 2-phenylpyridine, Hpyt = pyridine-2-thiol) and its oxidized platinum(Ill) complex, [Pt2Cl2(ppy)2(pyt)2] have been synthesized and characterized. The divalent complex exhibits intense red luminescence both in solution and in the solid states. Corresponding to the short Pt ... Pt distance (2.849(1) Å) for [Pt2(ppy)2(pyt)2], the reversible conversion between the divalent and trivalent complexes occurs easily with appearance and disappearance of the luminescence. [ABSTRACT FROM AUTHOR]

Examines the crystal structure of dichloro(4,4-dinonyl-2,2'-bipyridine- kappa[sup 2]N,N')platinum(II). Bipyridine moiety with two long alkyl-chain substituents contained in the complex; Complex forming a segregated packing structure made up of the alkyl-chain layers and paired coordination sites.

We synthesized a novel Pt(II)--diimine complex with a typical ambidentate thiocyanato ligand, [Pt(thiocyanato)2(H2dcbpy)] (1j H2dcbpy =4,4'-dicarboxy-2)2'-bipyridine), and found that the complex 1 exhibits unique linkage isomerizations with drastic color and luminescence changes driven by exposure to volatile organic chemical (VOC) vapors in the solid state. Reaction between [PtCl2(H2dcbpy)] and KSCN in aqueous solution at 0 °C enabled successful isolation of an isomer with the S-coordinated thiocyanato ligand, [Pt(SCN)2(H2dcbpy)] (1SS·H2O), as a nonluminescent orange solid, Interestingly, 1SS·H2O was isomerized completely to one isomer with the N-coordinated isothiocyanato ligand, [Pt(NCS)2(H2dcbpy)] (1NN·3DMF) by exposure to DMF vapor, and this isomerization was accompanied by significant color and luminescence changes from nonluminescent orange to luminescent red. IR spectroscopy and thermogravimetric analysis revealed that adsorption of the DMF vapor and transformation of the hydrogen-bonded structure both played important roles in this vapor-induced linkage isomerization. Another isomer containing both S- and N-coordinated thiocyanato ligands, [Pt(SCN)(NCS)(H2dcbpy)] (1SN), was obtained as a nonluminescent yellow solid simply by exposure of 1SS·H2O to acetone vapor at room temperature, and about 80% of 1SS&niddot;H2O was found to be converted to ISN. In the solution state, each isomer changed gradually to an isomeric mixture, but pure 1SS was regenerated by UV light irradiation (λirr = 300 nm) of an MeOH solution of the mixture. In the crystal structure of 1SN, the complex molecules were hydrogen-bonded to each other through the carboxyl groups of the H2dcbpy ligand and the N site of the thiocyanato ligand, whereas the 1NN molecules in the 1NN·4DMF crystal were hydrogen-bonded to the solvated DMF molecules. Competition of the hydrogen-bonding abihty among the carboxyl groups of the H2dcbpy ligand, N and S atoms of the thiocyanato ligand, and the vapor molecule was found to be one of the most important factors controlling linkage isomerization behavior in the solid state. This unique linkage isomerization controlled by vapor can provide an outstanding vapochromic system as well as a new molecular sTvitching function driven by vapor molecules. [ABSTRACT FROM AUTHOR]

The neutral square-planar complexes [Pt(RN)2)2(NHCOtBu)2] (R = H, 1; Et, 2) and [Pt(DACH)(NHCOtBu)2] (DACH = 1,2-diaminocyclohexane, 3) act as metalloligands and make bonds to closed-shell Tl(l) ions to afford one- and two-dimensional platinum-thallium oligomers or polymers based on heterobimetallic backbones. A series of heteronuclear platinum(II)-thallium(l) complexes have been synthesized and structurally characterized. The structures of the Pt-TI compounds resulted from [Pt(RN)2)2(NHCOtBu)2] and TIX [X = NO3-, ClO4-, PF6-, and Cp2Fe(Co2)22-] are dependent on both counteranions and the amine substituents. The compounds [Pt(NH3)2(NHCOtBu)2TI]+ (X = NO3, 8; ClO4-, 9) adopt one-dimensional zigzag chain structures consisting of repeatedly stacked [Pt(NH3)2-(NHCOtBu)2TI]+ units, whereas [{Pt(NH3)2(NHCOtBu)2}2TI2]X2 (X = PF6-, 10) consists of a helical chain. Compound 3 reacts with TI+ to give [{Pt(DACH)(NHCOtBu)2}2TI](NO3)-[Pt(DACH)(NHCOtBu)2]·3H2O (14) and one-dimensional polymeric [{Pt(DACH)(NHCOtBu)2}2TI2]X2 (X = ClO4-, 15; PF6-, 16). Reactions of [Pt(DACH)(NHCOCH3)2) with TI+ ions afford one-dimensional coordination polymers [{Pt(DACH)(NHCOCH3)2}2TI2]X2 (X = NO3-, 17; ClO4-, 18; PF6-, 19). The polymeric [{Pt(DACH)(NHCO′)2}TI2]2+ (R = CH3, tBu) complexes adopt helical structures, which are generated around the crystallographic 2 screw axis. The distance between the coils corresponds to the unit cell length, which ranges from 22.58 to 22.68 Å. The platinum-thallium bond distances fall in a narrow range around 3.0 Å. The complexes derived from [Pt(NH3)2(NHCOtBu)2] are luminescent at 77 K. The trinuclear complexes [{Pt(RN)2)(NHCOtBu)2}2TI]+ do not emit at room temperature but are emissive at 77 K, whereas the polymeric platinum-thallium complexes containing 1 ,2-diaminocyclohexane are intensively luminescent at both room temperature and 77 K. The color variations are interesting; 15 exhibits intense yellow-green, 16 exhibits green, and 17-19 exhibit blue luminescence. The presence of bonding between platinum and thallium is supported by the short metal-metal separations and the strong low-energy luminescence of these compounds in their solid states. [ABSTRACT FROM AUTHOR]