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Reaction of 4‐methylphenylacetylide with the known chlorido platinum(II) complex bearing the cyclometalated 1,3‐bis(pyridin‐2‐yl)‐4,6‐difluoro‐benzene ligand afforded a novel alkynyl platinum(II) complex, 1, that was fully characterized by elemental analysis, NMR and UV‐visible spectroscopies, by photoluminescence measurements, and by computational modelling. Its structure was determined by X‐ray diffraction studies on a single crystal whereas its second‐order nonlinear optical (NLO) properties were determined in solution by the Electric‐Field Induced Second Harmonic generation method. The novel multifunctional complex 1 is characterized by good luminescence properties, like the related chlorido Pt(II) complex, but by a much higher second‐order NLO response. [ABSTRACT FROM AUTHOR]

New Y-shaped ferrocene (Fc)-conjugated trifluoromethyl-substituted imidazole (IM) donor–π–acceptor [(D–π)2–IM–D′–π–CF3] "push–pull" chromophores [(Fc–CH＝CH)2–IM–C6H4–R–C6H4–CF3] {R= –OCH3 (1); –N(C2H5)2 (2)} were synthesized and structurally characterized. The structure of the chromophores was confirmed via single-crystal X-ray diffraction studies. They crystallized in the triclinic P1¯ (for 1) and monoclinic P21/c (for 2) space groups. Thermogravimetric analysis (TGA) was used to study the thermal stability of chromophores 1 and 2, and it was found that both were stable at temperatures of about 300 °C. The redox properties were studied through cyclic voltammetry (CV), which revealed one-electron transfer from the ferrocene to ferrocenium ion (Fe2+ Fe3+), and their potentials were utilized to calculate their energy gaps, which were 2.16 eV for 1 and 2.12 eV for 2. The second-order nonlinear optical (NLO) properties of chromophores 1 and 2 were explored via electric-field-induced second-harmonic generation (EFISH) technique in CHCl3 solution with an incident wavelength of 1907 nm. μβEFISH values were −725 × 10−48 esu and −806 × 10−48 esu for 1 and 2, respectively. The μβEFISH values slightly decreased compared with other reported ferrocene-conjugated Y-shaped imidazole chromophores owing to their substitution on imidazole nitrogen, which increases steric hindrance and reduces the ICT process in the chromophores. In addition, their frontier molecular orbital levels, excited and ground state dipole moments (μe and μg), and electronic absorption spectra were studied using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) with the B3LYP method using the 6-31+G** basis set. [ABSTRACT FROM AUTHOR]

Three decades ago, dye-sensitized solar cells (DSSCs) emerged as a route for harnessing the sun's energy and converting it into electricity. Since then, an impressive amount of work has been devoted to improving the global photovoltaic efficiency of DSSCs, trying to optimize all components of the device. Up to now, the best efficiencies have usually been reached with ruthenium(II) photosensitizers, even if in the last few years many classes of organic compounds have shown record efficiencies. However, the future of DSSCs is stringently connected to the research and development of cheaper materials; in particular, the replacement of rare metals with abundant ones is an important topic in view of the long-term sustainability of DSSCs intended to replace the consolidated fossil-based technology. In this context, copper is a valid candidate, being both an alternative to ruthenium in the fabrication of photosensitizers and a material able to replace the common triiodide/iodide redox couple. Thus, recently, some research papers have confirmed the great potential of copper(I) coordination complexes as a cheap and convenient alternative to ruthenium dyes. Similarly, the use of copper compounds as electron transfer mediators for DSSCs can be an excellent way to solve the problems related to the more common I3−/I− redox couple. The goal of this mini-review is to report on the latest research devoted to the use of versatile copper complexes as photosensitizers and electron shuttles in DSSCs. The coverage, from 2022 up to now, illustrates the most recent studies on dye-sensitized solar cells based on copper complexes as molecular materials. [ABSTRACT FROM AUTHOR]

The studies about the photophysical and electrochemical properties of [Ir[(ppy or pq).sub.2] (substituted-1,10-phenanthroline)]-[P[F.sub.6]] (ppy = 2-phenypyridine, pq = 2-phenylquinoline) is presented. The results provide insight into nature and number of the phenanthroline substituents to tune the color, quantum yield, and lifetime of the emission.

Coordination of 4'-(C6H4-p-X)-2,2':6',2'-terpyridines[X = NO2, NBu2, (E)-CH=CH-C6H4-p-NBu2, (E,E)-(CH=CH)2-C6H4-p-NMe2] to Zn(II), Ru(III), and Ir(III) metal centers induces a significant enhancement of the absolute value of their second-order nonlinear optical (NLO) response. Varying the nature of the metal center, the second order NLO response shifts from positive to negative, being controlled by metal-to-ligand, ligand-to-metal or intraligand charge-transfer transitions.

Reaction of [Me.sub.3]SiONa with [Re[(CO).sub.5]Cl] affords the new complex Na[[Re.sub.2][(CO).sub.6] [([micro]-Osi[Me.sub.3]).sub.3]], which could be generated via formation of [Re[(CO).sub.5]Osi[Me.sub.3]] followed by immediate reaction with [Me.sub.3]Si[O.sup.-]. Substitution of some CO ligands by phosphines significantly decreases the electrophilicity of the Re(I) center, and therefore hinders further attack by [Me.sub.3]Si[O.sup.-]. Thus, fac-[Re[(CO).sub.3]([Ph.sub.2]PC[H.sub.2]C[H.sub.2] P[Ph.sub.2])OTf] (OTf is the triflate anion) reacts with [Me.sub.3]SiONa to give fac-[Re[(CO).sub.3]([Ph.sub.2] PC[H.sub.2]C[H.sub.2]P[Ph.sub.2])Osi[Me.sub.3]], a molecular model of silica anchored [Re[(CO).sub.5]OSi [equivalent to]) However, substitution of only one CO by triphenylphosphine is not enough to avoid the formation of [[[Re.sub.2][(CO).sub.6] [([micro]-Osi[Me.sub.3]).sub.3]].sup.-]. While fac-[Re[(CO).sub.3]([Ph.sub.2]PC[H.sub.2]C[H.sub.2] P[Ph.sub.2])Osi[Me.sub.3]] is stable towards hydrolysis, [[Re.sub.2][(CO).sub.6] [([micro]-OSi[Me.sub.3]).sub.3].sup.-] is readily hydrolyzed to [[[Re.sub.2][(CO).sub.6]([micro]-OH) ([micro]-OSi[Me.sub.3]).sub.2]].sup.-] , a molecular model of silica anchored [[[Re.sub.2][(CO).sub.6]([micro]-OH) [([micro]-OSi [equivalent to].sub.2].sup.-], whose structure has been determined by single crystal X-ray diffraction. Key words: surface organometallic chemistry, rhenium, silica, silanolate, molecular model. La reaction de [Me.sub.3]SiONa avec [Re[(CO).sub.5]Cl] fournit le nouveau complexe Na[[Re.sub.2][(CO).sub.6][([micro]-OSi [Me.sub.3]).sub.3]], probablement genere via la formation de [Re[(CO).sub.5]OSi[Me.sub.3]] suivie par une reaction immediate avec [Me.sub.3]Si[O.sup.-]. La substitution de quelques CO par des phosphines diminue fortement l'electrophilicite du centre Re(I) et, par consequent, empeche toute attaque ulterieure par [Me.sub.3]Si[O.sup.-]. Ainsi, fac-[Re[(CO).sub.3]([Ph.sub.2]PC[H.sub.2]C[H.sub.2] P[Ph.sub.2])OTf] (OTf est l'anion triflate) reagit avec [Me.sub.3]SiONa pour donner fac-[Re[(CO).sub.3] ([Ph.sub.2]PC[H.sub.2]C[H.sub.2]P[Ph.sub.2])OSi[Me.sub.3]], modele moleculaire de l'espece ancree a la silice [Re[(CO).sub.5]OSi [equivalent to]]. Cependant la substitution d'un seul CO par la triphenylphosphine ne suffit pas a empecher la formation de [[[Re.sub.2][(CO).sub.6]([micro]-OSi[Me.sub.3]).sub.3]].sup.-]. Alors que fac-[[Re[(CO).sub.3]([Ph.sub.2]P[CH.sub.2][CH.sub.2] P[Ph.sub.2])OSi][Me.sub.3]] est stable en presence d'eau, [[Re.sub.2]](CO).sub.6] ([micro]-OSi[Me.sub.3]).sub.3].sup.-] s'hydrolyse rapidement pour donner [[[Re.sub.2][(CO).sub.6]([micro]-OH) ([micro]-OSi[Me.sub.3]).sub.2]].sup.-], modele moleculaire de l'espece ancree a la silice [[Re.sub.2][(CO).sub.6]([micro]-OH)([micro]-OSi [equivalent to])2].sup.-], dont la structure a ete determinee par diffraction des rayons X. Mots cles : chimie organometallique de surface, rhenium, silice, silanolate, modele moleculaire.

The structural, emissive, and nonlinear optical properties of new CuI adducts with para-substituted trans-stibazolic and pyridinic ligands are reported. Single-crystal X-ray diffraction results indicate that the para-substituent on the organic ligand greatly influences the structural motif by its steric, electronic/steric, or bridging-donor properties.