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A heterometallic Tb-Pt complex, [Tb2 Pt3 (SAc)12 (H2 O)2 ] (SAc=thioacetate), was synthesized. Dual emission was modulated by the presence of a heterometallic Tb-Pt bonding environment. The heterometallic Tb-Pt bond lowers the symmetry of the Tb ion and enhanced the emission efficiency. In addition, the Tb-Pt complex shows field-induced multiple magnetic relaxation pathways. Furthermore, it served as an antenna for the observed dual emission. In other words, the heterometallic Tb-Pt bond has a significant effect on the luminescence and magnetic properties of the complex.

The first three–dimensional (3D) conductive single-ion magnet (SIM), (TTF)2[Co(pdms)2] (TTF = tetrathiafulvalene and H2pdms = 1,2-bis(methanesulfonamido)benzene), was electrochemically synthesized and investigated structurally, physically and theoretically. The quite close oxidation potential between neutral TTF and the coordination precursor, (HNEt3)2[M(pdms)2] (M = Co, Zn) causes multiple charge transfers (CTs) between SIM donor [M(pdms)2]n– and the TTF●+ acceptor as well as an intra-donor CT from the pdms ligand to Co ion upon electrocrystallization. Usually TTF works as a donor, whereas in our system, TTF works as both a donor and an accepter due to the close oxidation potentials. Furthermore, the [M(pdms)2]n– donor and TTF●+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor-acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with the CT, cause relatively high electrical conductivity to very low temperature. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops were observed. (TTF)2[Co(pdms)2] (2-Co) is an excellent building block for preparing new conductive SIM.

International audience; (TTF-salphen)M compounds (TTF-salphen(2-)=4,5-bis(propylthio)tetrathiafulvalene-N,N'-phenylenebis(salicylideneimine) dianion; M=Cu(II) and Ni(II)) have been treated with Ln(hfac)(3)*2H(2)O precursors (hfac(-)=1,1,1,5,5,5-hexafluoroacetylacetonate anion; Ln=Gd(III), Tb(III), and Dy(III)) to elaborate unprecedented 3d/4f TTF-based heterobimetallic complexes of formula [(TTF-salphen)MLn(hfac)(3)]. All the structures of these compounds have been resolved by X-ray diffraction on single crystals. The structures of these complexes are formed by a TTF-salphen(2-) ligand coordinated to the 3d metal ions in the inert tetradentate N(2)O(2) site. The Ln(hfac)(3) fragment is coordinated to the (TTF-salphen)M one through the two phenolate bridges. Even if the complexes are similar in both Cu(II) and Ni(II) families, the crystal packing is different. In the first case, dimers of TTF-salphen(2-) donors constitute the organic network. In the other case, a reminiscent organic network is observed with S***S contacts. The photophysical properties of [(TTF-salphen)CuDy(hfac)(3)] (3) in chloroform solution highlight the redshift of the TTF→salphen charge transfer (400 cm(-1)) relative to the analogue excitations in (TTF-salphen)Cu, which attest to the stability of these structures in solution. Static magnetic measurements have allowed us to quantify the ferromagnetic interactions (J=+1.29 cm(-1)) between Cu(II) and Gd(III) in the [(TTF-salphen)CuGd(hfac)(3)] complex. Finally, an empirical method that consists of the comparisons of the magnetic properties of [(TTF-salphen)CuTb(hfac)(3)] with [(TTF-salphen)NiTb(hfac)(3)] and [(TTF-salphen)CuDy(hfac)(3)] with [(TTF-salphen)NiDy(hfac)(3)] has established that ferromagnetic interactions take place between Cu(II) and Tb(III) ions, whereas unusual antiferromagnetic interactions have been identified between Cu(II) and Dy(III) ions.