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1.
Inorg Chem ; 54(11): 5384-97, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25965094

RESUMO

The reaction between the TTF-fused dipyrido[3,2-a:2',3'-c]phenazine (dppz) ligand (L) and 1 equiv of Ln(hfac)3·2H2O (hfac(-) = 1,1,1,5,5,5-hexafluoroacetyacetonate) or 1 equiv of Ln(tta)3·2H2O (tta(-) = 2-thenoyltrifluoroacetonate) (Ln(III) = Dy(III) or Yb(III)) metallic precursors leads to four mononuclear complexes of formula [Ln(hfac)3(L)]·C6H14 (Ln(III) = Dy(III) (1), Yb(III) (2)) and [Ln(tta)3(L)]·C6H14 (Ln(III) = Dy(III) (3), Yb(III) (4)), respectively. Their X-ray structures reveal that the Ln(III) ion is coordinated to the bischelating nitrogenated coordination site and adopts a D4d coordination environment. The dynamic magnetic measurements show a slow relaxation of the Dy(III) magnetization for 1 and 3 with parameters highlighting a slower relaxation for 3 than for 1 (τ0 = 4.14(±1.36) × 10(-6) and 1.32(±0.07) × 10(-6) s with Δ = 39(±3) and 63.7(±0.7) K). This behavior as well as the orientation of the associated magnetic anisotropy axes have been rationalized on the basis of both crystal field splitting parameters and ab initio SA-CASSCF/RASSI-SO calculations. Irradiation of the lowest-energy HOMO → LUMO ILCT absorption band induces a (2)F5/2 → (2)F7/2 Yb-centered emission for 2 and 4. For these Yb(III) compounds, Stevens operators method has been used to fit the thermal variation of the magnetic susceptibilities, and the resulting MJ splittings have been correlated with the emission lines.

2.
Inorg Chem ; 54(8): 4021-8, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25831451

RESUMO

The reaction between the 2-(1-(2,6-di(pyrazol-1-yl)-4-methylpyridyl)-4,5-(4,5-bis(propylthio)-tetrathiafulvalenyl)-1H-benzimidazol-2-yl)-pyridine ligand (L) and 2 equiv of Dy(hfac)3·2H2O (hfac(-) = 1,1,1,5,5,5-hexafluoroacetylacetonate) and 1 equiv each of Dy(hfac)3·2H2O and Dy(tta)3·2H2O (tta(-) = 2-thenoyltrifluoroacetonate) metallic precursors leads to two dinuclear complexes, [Dy2(hfac)6(L)]·(CH2Cl2)2·C6H14 (1) and [Dy2(hfac)3(tta)3(L)] (2), respectively. Their X-ray structures reveal that the two coordination sites are occupied by one Dy(III) ion. The Dy(III) ion coordinated to the benzoimidazolylpyridine (bzip) moiety adopts a D4d coordination sphere, while the Dy(III) ion coordinated to the 2,6-di(pyrazol-1-yl)-4-pyridine (dpp) moiety is in a D3h surrounding. In a zero dc field, the dynamic magnetic measurements show a slow relaxation for the D4d eight-coordination Dy(III) magnetization for 1 and 2. Application of an external dc field induces multirelaxation signals of the magnetic susceptibility for both compounds. The low frequency and high frequency of the out-of-phase magnetic signals are attributed to the Dy(III) ion in D4d and D3h surroundings, respectively. The two complexes can be described as double induced-field mononuclear single-molecule magnets.

3.
Angew Chem Int Ed Engl ; 54(5): 1504-7, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25486900

RESUMO

The influence of nuclear spin on the magnetic hysteresis of a single-molecule is evidenced. Isotopically enriched Dy(III) complexes are synthesized and an isotopic dependence of their magnetic relaxation is observed. This approach is coupled with tuning of the molecular environment through dilution in an amorphous or an isomorphous diamagnetic matrix. The combination of these approaches leads to a dramatic enhancement of the magnetic memory of the molecule. This general recipe can be efficient for rational optimization of single-molecule magnets (SMMs), and provides an important step for their integration into molecule-based devices.

4.
Chem Asian J ; 9(10): 2814-25, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25087945

RESUMO

Ligand L was synthesized and then coordinated to [Ln(hfac)3]⋅2 H2O (Ln(III)=Tb, Dy, Er; hfac(-)=1,1,1,5,5,5-hexafluoroacetylacetonate anion) and [Ln(tta)3]⋅2 H2O (Ln(III)=Eu, Gd, Tb, Dy, Er, Yb; tta(-)=2-thenoyltrifluoroacetonate) to give two families of dinuclear complexes [Ln2(hfac)6(L)]⋅C6H14 and [Ln2(tta)6(L)]⋅2 CH2Cl2. Irradiation of the ligand at 37,040 cm(-1) and 29,410 cm(-1) leads to tetrathiafulvalene-centered and 2,6-di(pyrazol-1-yl)-4-pyridine-centered fluorescence, respectively. The ligand acts as an organic chromophore for the sensitization of the infrared Er(III) (6535 cm(-1)) and Yb(III) (10,200 cm(-1)) luminescence. The energies of the singlet and triplet states of L are high enough to guarantee an efficient sensitization of the visible Eu(III) luminescence (17,300-14,100 cm(-1)). The Eu(III) luminescence decay can be nicely fitted by a monoexponential function that allows a lifetime estimation of (0.49±0.01) ms. Finally, the magnetic and luminescence properties of [Yb2(hfac)6(L)]⋅C6H14 were correlated, which allowed the determination of the crystal field splitting of the (2)F(7/2) multiplet state with M(J)=±1/2 as ground states.

5.
Chem Commun (Camb) ; 49(99): 11632-4, 2013 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-24177382

RESUMO

Lanthanide dinuclear complexes involving tetrathiafulvalene-based ligands in their radical cation form were synthesised and crystallised by a galvanostatic procedure. Dynamic magnetic measurements reveal an unprecedented slow magnetic relaxation for the Dy(III) analogue in this kind of molecular edifice.

6.
J Am Chem Soc ; 135(44): 16332-5, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24127637

RESUMO

The [Dy(tta)3(L)] complex behaves as a single ion magnet both in its crystalline phase and in solution. Experimental and theoretical magnetic anisotropy axes perfectly match and lie along the most electro-negative atoms of the coordination sphere. Both VSM and MCD measurements highlight the robustness of the complex, with persistence of the memory effect even in solution up to 4 K.

7.
Inorg Chem ; 52(17): 9711-3, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23944607

RESUMO

The galvanostatic reaction of the [4,5-bis(2-pyridyl-N-oxidemethylthio)]-4',5'-methyldithiotetrathiafulvalene ligand with lanthanide ions in the presence of hexafluorophosphate (PF6(-)) anions afforded the highest-nuclearity lanthanide clusters decorated by tetrathiafulvalene-based ligands thanks to the original partial hydrolysis of the PF6(-) anions in difluorodioxophosphate (PO2F2(-)) bridging ligands.

8.
J Phys Chem A ; 117(25): 5241-50, 2013 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-23768132

RESUMO

Polarized reflectivity spectra versus temperature of two isostructural charge-transfer salts κ-(ET)4[M(CN)6][N(C2H5)4]·2H2O (M = Co(III) and Fe(III)) (ET = bis(ethylenedithio)tetrathiafulvalene) were studied. The electronic and vibrational spectra exhibit a drastic change at around 150 K. On the basis of the spectral analysis, we deduced the nature of the phase transition. The phase transition at 150 K is due to a charge ordering; above this temperature, strong charge fluctuations are observed.

9.
Inorg Chem ; 52(10): 5978-90, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23659581

RESUMO

The reaction between (4,5-bis(2-pyridyl-N-oxidemethylthio)-4',5')-ethylenedithiotetrathiafulvene (L(1)) or -methyldithiotetrathiafulvene (L(2)) ligands and Ln(hfac)3·nH2O precursors (Ln(III) = Pr, Tb, Dy, Er, and Yb) leads to the formation of seven dinuclear complexes of formula [Ln2(hfac)6(H2O)x(L(y))2] (x = 2 and y = 1 for Ln(III) = Pr (1); x = 0 and y = 1 for Ln(III) = Tb (2), Dy (3), Er (4) and Yb (5); x = 0 and y = 2 for Ln(III) = Tb (6) and Dy (7)). Their X-ray structures reveal that the coordination environment of each Ln(III) center is filled by two N-oxide groups coming from two different ligands L(y). UV-visible absorption properties have been experimentally measured and rationalized by TD-DFT calculations. The temperature dependences of static magnetic measurements have been fitted. The ground state corresponds to the almost pure |M(J) = ±13/2〉 while the first excited state (±0.77|±11/2〉 ± 0.50|±3/2〉 ± 0.39|±5/2〉) is located at 19 cm(-1) and 26.9 cm(-1) respectively for 3 and 7. Upon irradiation at 77 K and at room temperature, in the range 25,000-20,835 cm(-1), both compounds 4 and 5 display a metal-centered luminescence attributed to (4)I(13/2) → (4)I(15/2) (6660 cm(-1)) and (2)F(5/2) → (2)F(7/2) (9972 cm(-1)) transitions, respectively. Emission spectroscopy provides a direct probe of the |±5/2〉 ground state multiplet splitting, which has been confronted to magnetic data. The energy separation of 225 cm(-1) between the ground state and the first excited level (M(J) = ±3/2) fits exactly the second emission line (234 cm(-1)). While no out-phase-signal is detected for 3, the change of ligand L(1) → L(2) induces a change of coordination sphere symmetry around the Dy(III) increasing the energy splitting between the ground and first excited states, and 7 displays a single molecule magnet behavior.


Assuntos
Compostos Heterocíclicos/química , Elementos da Série dos Lantanídeos/química , Luminescência , Imãs/química , Compostos Organometálicos/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Processos Fotoquímicos
10.
Chemistry ; 19(24): 7895-903, 2013 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-23589325

RESUMO

Reaction of the ligands 4,5-bis(propylthio)tetrathiafulvalene-2-(2-pyridyl)benzimidazole (L(1)) and 4,5-bis(propylthio)tetrathiafulvalene-2-(2-pyridyl)-3-(2-pyridinylmethyl)benzimidazole (L(2)) with Dy(hfac)3⋅2 H2O (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate) gave mononuclear complexes [Dy(hfac)3(L(1))] (1) and [Dy(hfac)3(L(2))] (2). In both compounds the Dy(III) ion is surrounded by six oxygen and two nitrogen atoms. Complex 1 displays single-ion magnet (SIM) behaviour only in solution (Δ=12(1) K and τ0 =1.9(4)×10(-6)  s), while complex 2 is a SIM in both solution (Δ=15(2) K and τ0 =1.5(3)×10(-6)  s) and solid state (Δ=17(2) K and τ0 =9.5(2)×10(-6)  s). The SIM behaviour is obtained if the hydrogen bond is broken by dissolution (1 in solution) or by alkylation (2). Multiple relaxation processes were identified for 2 with two competing processes: a fast one in zero field and a slow one for fields higher than 500 Oe. The two processes coexist for intermediate applied magnetic field. Magnetic-dilution and frozen-solution measurements led to the conclusion that the origin of these multiple relaxation processes is not due to the property of a single molecule.

11.
Inorg Chem ; 52(3): 1398-408, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23339398

RESUMO

Centro-symmetric dinuclear complexes of formula [Ln(tta)(3)(L)](2)·xCH(2)Cl(2), (tta(-) = 2-thenoyltrifluoroacetonate anion, x = 0.5 for Ln = Eu (1a), Tb (3), and Dy (4) and x = 0 for Ln = Eu (1b) and Nd (2)) have been synthesized using the tetrathiafulvalene-3-pyridine-N-oxide as a bridging ligand (L). X-ray structures have shown the formation of channels with CH(2)Cl(2) solvent inside. 1 is stable with both filled channels (at 150 K) and empty channels (at room temperature). The Dy(III) analogue displays a complex butterfly like hysteresis loop at 1.5 K. Photophysical properties of the coordination complexes have been studied by solution and solid-state absorption spectroscopy. Time-dependent density functional theory (TD-DFT) calculations have been carried out on the diamagnetic Y(III) derivative to shed light on the absorption spectrum. For 2, the excitation of the charge transfer transitions induces line shape emission in the near-infrared spectral range assigned to (4)F(3/2) → (4)I(9/2), (4)F(3/2) → (4)I(11/2), and (4)F(3/2) → (4)I(13/2) neodymium centered transitions. The reversible redox-activity of the ligand L makes possible an original sensitization process involving a ligand centered charge separation followed by energy transfer to the Nd(III) ion upon recombination.


Assuntos
Óxidos N-Cíclicos/química , Elementos da Série dos Lantanídeos/química , Compostos Organometálicos/química , Radicais Livres/química , Ligantes , Campos Magnéticos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Processos Fotoquímicos , Teoria Quântica , Sais/química , Semicondutores
12.
Inorg Chem ; 52(3): 1610-20, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23323869

RESUMO

The reaction between the tetrakis(2-pyridyl-N-oxidemethylthio)tetrathiafulvalene ligand (L) and Ln(hfac)(3)·2H(2)O precursors (where hfac(-) = 1,1,1,5,5,5-hexafluoroacetylacetonate anion and Ln = Tb(III) (1), Dy(III) (2), Er(III) (3), and Yb(III) (4) and (4b)) leads to the formation of five tetranuclear complexes of formula [Ln(4)(hfac)(12)(L)(2)](n)·xCHCl(3)·yC(6)H(14) (n = 1, x = 2, y = 0 for (1), (2), and (4), n = 1, x = 4 for (3), and n = 2, x = 2.5, y = 1 for (4b)). Their X-ray structures reveal that the surrounding of each Ln(III) center is filled by two N-oxide groups coming from two different ligands L. These tetranuclear complexes have the highest nuclearity which is reported until now for coordination compounds of lanthanide involving TTF-based ligands. Direct current (dc) measurements highlight the paramagnetic behavior of the compounds with a significant crystal field effect. The temperature dependences of static magnetic measurements for 4 have been fitted. The ground state corresponds to M(J) = ±5/2 while the first excited state (M(J) = ±3/2) was localized at +214 cm(-1) which was well correlated with the luminescence transition. UV-visible absorption properties have been experimentally measured and rationalized by time-dependent density functional theory (TD-DFT) calculations. Upon irradiation at 77 K and room temperature, in the range 24390-20835 cm(-1), both compounds 3 and 4 display a metal-centered luminescence attributed to (4)I(13/2) → (4)I(15/2) (6660 cm(-1)) and (2)F(5/2) → (2)F(7/2) (signal centered around the value of 9966 cm(-1)) transitions, respectively. The observed six transitions could be attributed to the M(J) state splitting due to the existence of two Yb1 and Yb2 ions with slightly different polyhedra in 4.


Assuntos
Compostos Heterocíclicos/química , Elementos da Série dos Lantanídeos/química , Compostos Organometálicos/química , Ligantes , Campos Magnéticos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Processos Fotoquímicos
13.
Chem Commun (Camb) ; 49(6): 615-7, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23223163

RESUMO

A redox active dinuclear complex [Yb(tta)(2)(L(1))(L(2))](2)·1.4(CH(2)Cl(2)) displays single molecule magnet behaviour with M(J) = ±7/2 ground state. The anisotropic barrier Δ is evaluated by the three dc data fit, ac analysis and emission spectrum demonstrating the correlation between magnetic and optical properties.

14.
Dalton Trans ; 42(6): 1949-60, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23208602

RESUMO

The elaboration of multifunctional materials is a great challenge for the physical chemistry community and the studies of molecular materials exhibiting coexistence or synergy between two or more properties are very active. In particular, molecular compounds displaying electrical conductivity and magnetic interactions are currently the subject of intensive studies. Two approaches are now well-known and are explored. On the one hand, the interactions between mobile electrons of the organic network (π electrons) and localized electrons of paramagnetic transition metal (d electrons) take place through space. On the other hand, these interactions take place through covalent chemical bonds. In the latter, the probability to have significant interaction between π and d electrons is enhanced compared to the first approach. In this perspective article, we will give an overview of the known coordination complexes involving tetrathiafulvalene derivatives as ligands for paramagnetic 3d ions and we will describe their physical properties. If necessary, the coexistence or synergy between electrical conductivity, magnetism and other properties will be highlighted.

15.
Inorg Chem ; 51(15): 8488-501, 2012 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-22784369

RESUMO

Six new 3d4f heterobimetallic dinuclear complexes, [(L(1))MLn(hfac)(3)] [M = Cu(II), Ni(II); Ln = Y(III), Er(III), Yb(III); L(1) = 4,5-bis(propylthio)tetrathiafulvalene-N,N'-phenylenebis(salicylideneimine) and hfac(-) = 1,1,1,5,5,5-hexafluoroacetylacetonate], and one tetranuclear complex, [(L(2))Cu(OH)Er(hfac)(3)](2) (where L(2) = 4,5-bis(propylthio)tetrathiafulvalene-N,N'-phenyleneaminosalicylideneimine), have been synthesized. All of the X-ray structures of the coordination complexes have been resolved from single-crystal diffraction. A quantitative magnetic approach has allowed one to determine the Cu-Ln ferromagnetic interaction for Gd(III) (1.29 cm(-1)) and Tb(III) (0.40 cm(-1)) and the antiferromagnetic interaction for Dy(III) (-0.46 cm(-1)) and Yb(III) (-2.25 cm(-1)), while in the case of Er(III), the magnetic interactions are negligible. The UV-visible absorption properties have been studied in a chloroform solution and rationalized by DFT and TD-DFT calculations. Upon oxidation, intramolecular SOMO → LUMO (20,800 cm(-1)) and SOMO-n → SOMO (11,350 cm(-1)) charge transfers appear, while the HOMO → LUMO charge transfers (20,750 cm(-1)) disappear. The reversibility of the oxidation has been confirmed by electrochemistry and absorption properties upon the addition of a reducing agent. Irradiation at the HOMO → LUMO charge-transfer energy of the dinuclear complex [(L(1))NiY(hfac)(3)] induces a ligand-centered fluorescence at 14,450 cm(-1).

16.
Chemistry ; 18(16): 5006-12, 2012 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-22407897

RESUMO

Trinuclear building block {Fe(2)NiO(Piv)(6)} (Piv = pivalate), which possessed pseudo-D(3h) symmetry, was linked by two ligands, pseudo-D(3h) ligand tris-(4-pyridyl)pyridine (L1) and C(2v) ligand 4-(N,N-dimethylamino)phenyl-2,6-bis(4-pyridyl)pyridine (L2) into two products with different topologies: 2D coordination polymer [Fe(2)NiO(Piv)(6)(L1)](n) (1), and discrete molecule [{Fe(2)NiO(Piv)(6)}(8) {L2}(12)], which had a nanocube structure (2). In compound 1, trinuclear {Fe(2)NiO(Piv)(6)} blocks were linked through ligand L1 into layers with honeycomb topology. In compound 2, eight trinuclear blocks were located in the vertices of the nanocube, with each L2 ligand linked to two {Fe(2)NiO(Piv)(6)} units. In the crystal structure, these nanocubes formed infinite catenated chains. Analysis of possible structures that could be assembled from these building blocks showed that compounds 1 and 2 corresponded to their respective predicted topologies. Compound [1⋅solvent] possessed a porous structure, in which the voids were filled by solvent molecules (DMF or DMSO). This structure was retained following desolvation, and compound 1 absorbed significant quantities of N(2) and H(2) at 78 K (S(BET) = 730 m(2) g(-1), H(2) sorption capacity: 0.9 % by weight at 865 Torr). Desolvation of [2⋅solvent] led to disorder of its crystal structure, and compound 2 only adsorbed negligible quantities of N(2) but adsorbed 0.27 % H(2) (by weight) at 855 Torr and 78 K. The magnetic properties of these complexes (temperature dependence of molar magnetic susceptibility) were governed by the magnetic properties of the trinuclear "building block".

17.
Inorg Chem ; 51(2): 978-84, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22208478

RESUMO

In the [Er(hfac)(3)(L)](2) complex (1) (L = 4-tetrathiafulvalene-2,6-pyridinecarboxylic acid dimethyl ester), the Er(III) ion is bonded to the tridentate coordination site. Electrochemical and photophysical measurements in solution reveal that the tetrathiafulvalene moiety is a versatile antenna for erbium luminescence sensitization at 6540 cm(-1) upon excitation in the low-energy charge transfer transition (donor to acceptor charge transfer) at 16600 cm(-1) assigned via time-dependent density functional theory calculations.

18.
Chem Commun (Camb) ; 48(5): 714-6, 2012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-22129833

RESUMO

A Dy(III)-based dinuclear complex was synthesised and characterised by X-ray diffraction on single crystal and magnetic investigations. Dynamic magnetic measurements reveal a single molecule magnet behaviour for 1 which can be described as two single-ion magnets in a D(3h) local symmetry bridged by an acceptor-donor-acceptor ligand.

19.
J Org Chem ; 76(23): 9720-32, 2011 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-22017231

RESUMO

The stereoselective convergent total syntheses of both enantiomers of the tetrahydroisoquinoline (THIQ) alkaloid crispine A are described. The THIQ precursors (-)-6 (90:10 dr) and (-)-11 (85:15 dr) were prepared from the alkylation-reduction sequence of a common α-amino nitrile (+)-4 derivative that has been conveniently prepared by anodic cyanation. Elaboration of the pyrrolidine ring of the title compound was cleanly achieved by two efficient ring closures methods involving (a) the displacement of a halogen atom and (b) the formation of a cyclic iminium cation to afford (-)-crispine A in 90% and 85% yields, respectively. A crystallization of enantioenriched (-)-crispine A (90:10 er) with 1 equiv of (-)-DBTA afforded the tartrate salt (-)-14 (≥98:2 dr) in 81% yield. The absolute S configuration of (-)-crispine A was simply deduced from examination of the X-ray data of tartrate salt (-)-14. Likewise, the natural (+)-crispine A was prepared in seven workup steps in an overall 30% yield, and reciprocal crystallization with (+)-DBTA afforded the enantiomeric tartrate salt (+)-14 in a ≥98:2 dr. Both enantiomers of crispine A were liberated from their respective DBTA salts in ≥98:2 er's which were determined by proton and carbon NMR spectroscopy, utilizing (R)-(+)-tert-butylphenylphosphinothioic acid (+)-15 as chiral solvating agent.


Assuntos
Isoquinolinas/química , Isoquinolinas/síntese química , Eletroquímica , Estrutura Molecular , Estereoisomerismo
20.
Chemistry ; 17(44): 12502-11, 2011 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-21938745

RESUMO

(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.

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