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1.
Ligand π‐Radical Interaction with f‐Shell Unpaired Electrons in Phthalocyaninato–Lanthanoid Single‐Molecule Magnets: A Solution NMR Spectroscopic and DFT Study
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Marko Damjanović Takaumi Morita Prof. Keiichi Katoh Prof. Masahiro Yamashita Prof. Markus Enders 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14421-14432
The phthalocyaninato double‐decker complexes [M(obPc)2]0 (M= YIII, TbIII, DyIII; obPc=2,3,9,10,16,17,23,24‐octabutoxyphthalocyaninato), along with their reduced ([M(obPc)2]?[P(Ph)4]+; M=TbIII, DyIII) and oxidized ([M(obPc)2]+[SbCl6]? (M=YIII, TbIII) counterparts were studied with 1H, 13C and 2D NMR. From the NMR data of the neutral (i.e., with one unpaired electron in the ligands) and anionic TbIII complexes, along with the use of dispersion corrected DFT methods, it was possible to separate the metal‐centered and ligand‐centered contributions to the hyperfine NMR shift. These contributions to the 1H and 13C hyperfine NMR shifts were further analyzed in terms of pseudocontact and Fermi contact shifts. Furthermore, from a combination of NMR data and DFT calculations, we have determined the spin multiplicity of the neutral complexes [M(obPc)2]0 (M=TbIII and DyIII) at room temperature. From the NMR data of the cationic TbIII complex, for which actually no experimental structure determination is available, we have analyzed the structural changes induced by oxidation from its neutral/anionic species and shown that the interligand distance decreases upon oxidation. The fast electron exchange process between the neutral and anionic TbIII double‐decker complexes was also studied. 相似文献
2.
Redox‐Driven Symmetry Change for Terbium(III) Bis(porphyrinato) Double‐Decker Complexes by the Azimuthal Rotation of the Porphyrin Macrocycles
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Dr. Ken‐ichi Yamashita Takayo Yamanaka Naoya Sakata Prof. Dr. Takuji Ogawa 《化学:亚洲杂志》2018,13(13):1692-1698
Molecular structures for three oxidation forms (anion, radical, and cation) of terbium(III) bis(porphyrinato) double‐decker complexes have been systematically studied. We found that the redox state controls the azimuthal rotation angle (φ) between the two porphyrin macrocycles. For [TbIII(tpp)2]n (tpp: tetraphenylporphyrinato, n=?1, 0, and +1), φ decreases at each stage of the oxidation process. The decrease in φ is due to the higher steric repulsion between the phenyl rings on the porphyrin macrocycle and the β hydrogen atoms on the other porphyrin macrocycle, which results from the shorter interfacial distance between the two porphyrin macrocycles. Conversely, φ=45° for both [TbIII(oep)2]?1 and [TbIII(oep)2]0 (oep: octaethylporphyrinato), but φ=36° for [TbIII(oep)2]+1. Theoretical calculations suggest that the smaller azimuthal rotation angle of the cation form is due to the electronic interaction in the doubly oxidized ligand system. 相似文献
3.
Carolina R. Ganivet Dr. Beatriz Ballesteros Dr. Gema de la Torre Dr. Juan M. Clemente‐Juan Prof. Eugenio Coronado Prof. Tomás Torres 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(4):1457-1465
A series of homoleptic ([TbIII(Pc)2]) and heteroleptic ([TbIII(Pc)(Pc′)]) TbIII bis(phthalocyaninate) complexes that contain different peripheral substitution patterns (i.e., tert‐butyl or tert‐butylphenoxy groups) have been synthesized in their neutral radical forms and then reduced into their corresponding anionic forms as stable tetramethylammonium/tetrabutylammonium salts. All of these compounds were spectroscopically characterized and their magnetic susceptibility properties were investigated. As a general trend, the radical forms exhibited larger energy barriers for spin reversal than their corresponding reduced compounds. Remarkably, heteroleptic complexes that contain electron‐donor moieties on one of the two Pc ligands show higher effective barriers and blocking temperatures than their homoleptic derivatives. This result is assigned to the elongation of the N? Tb distances in the substituted macrocycle, which brings the terbium(III) ion closer to the unsubstituted Pc, thus enhancing the ligand‐field effect. In particular, heteroleptic [TbIII(Pc)(Pc′)] complex 4 , which contains one octa(tert‐butylphenoxy)‐substituted Pc ring and one bare Pc ring, exhibits the highest effective barrier and blocking temperature for a single‐molecule magnet reported to date. 相似文献
4.
Dr. Jong Min Lim Dr. Mei‐Jin Lin Dr. Ivo Krummenacher Prof. Dr. Holger Braunschweig Prof. Dr. Dongho Kim Prof. Dr. Frank Würthner 《Angewandte Chemie (International ed. in English)》2015,54(47):13980-13984
Unprecedented neutral perylene‐3,4:9,10‐tetracarboxylic acid bisimide (PBI) radicals and biradicals were synthesized by facile chemical oxidation of 4‐hydroxyaryl‐substituted PBIs. Subsequent characterization by optical and magnetic spectroscopic techniques, as well as quantum chemical calculations, revealed an open‐shell singlet biradical ground state for the PBI biradical OS ‐ 2.. (〈s2〉=1.2191) with a relatively small singlet–triplet energy gap of 0.041 eV and a large singlet biradical character of y=0.72. 相似文献
5.
Sandeep Nadella Dr. Paulraj M. Selvakumar Dr. Eringathodi Suresh Dr. Palani S. Subramanian Prof. Dr. Markus Albrecht Dr. Michael Giese Dr. Roland Fröhlich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(52):16784-16792
Phenanthroline‐based hexadentate ligands L1 and L2 bearing two achiral semicarbazone or two chiral imine moieties as well as the respective mononuclear complexes incorporating various lanthanide ions, such as LaIII, EuIII, TbIII, LuIII, and YIII metal ions, were synthesized, and the crystal structures of [ML1Cl3] (M=LaIII, EuIII, TbIII, LuIII, or YIII) complexes were determined. Solvent or water molecules act as coligands for the rare‐earth metals in addition to halide anions. The big LnIII ion exhibits a coordination number (CN) of 10, whereas the corresponding EuIII, TbIII, LuIII, and YIII centers with smaller ionic radii show CN=9. Complexes of L2, namely [ML2Cl3] (M=EuIII, TbIII, LuIII, or YIII) ions could also be prepared. Only the complex of EuIII showed red luminescence, whereas all the others were nonluminescent. The emission properties of the Eu derivative can be applied as a photophysical signal for sensing various anions. The addition of phosphate anions leads to a unique change in the luminescence behavior. As a case study, the quenching behavior of adenosine‐5′‐triphosphate (ATP) was investigated at physiological pH value in an aqueous solvent. A specificity of the sensor for ATP relative to adenosine‐5′‐diphosphate (ADP) and adenosine‐5′‐monophosphate (AMP) was found. 31P NMR spectroscopic studies revealed the formation of a [EuL2(ATP)] coordination species. 相似文献
6.
Switching of Single‐Molecule Magnetic Properties of TbIII–Porphyrin Double‐Decker Complexes and Observation of Their Supramolecular Structures on a Carbon Surface
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Tomoko Inose Dr. Daisuke Tanaka Prof. Dr. Hirofumi Tanaka Dr. Oleksandr Ivasenko Prof. Dr. Toshi Nagata Yusuke Ohta Prof. Dr. Steven De Feyter Prof. Dr. Naoto Ishikawa Prof. Dr. Takuji Ogawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(36):11362-11369
Double‐decker complexes based on single‐molecule magnets (SMMs) are a class of highly promising molecules for applications in molecular spintronics, wherein control of both the ligand oxidative states and the 2D supramolecular structure on carbon materials is of great importance. This study focuses on the synthesis and study of 2,3,7,8,12,13,17,18‐octaethylporphyrin (OEP)–TbIII double‐decker complexes with different electronic structures comprising protonated, anionic, and radical forms. Magnetic susceptibility measurements revealed that only the anionic and radical forms of the OEP–TbIII double‐decker complexes exhibited SMM properties. The barrier heights for magnetic moment reversal were estimated to be 207 and 215 cm?1 for the anionic and radical forms, respectively. Scanning tunneling microscopy (STM) investigations revealed that these OEP–TbIII complexes form well‐ordered monolayers upon simple dropcasting from dilute dichloromethane solutions. All three complexes form an isomorphic pseudo‐hexagonal 2D pattern, regardless of the differences in the electronic structures of their porphyrin–Tb cores. This finding is of interest for SMM technology as ultrathin films of these materials undergoing chemical transformations will not require any detrimental reorganization. Finally, we demonstrate self‐assembly of the protonated 5,15‐bisdodecylporphyrin (BDP)–TbIII double‐decker complex as an example of successful supramolecular design to achieve controlled alignment of SMM‐active sites. 相似文献
7.
The magnetic coupling interactions of the nitronyl nitroxide radicals bound to diamagnetic (YIII) and paramagnetic (GdIII) rare earth ions in two model magnetic systems based on novel rare earth organic radical complexes Ln(hfac)3(NITPhOCH3)2 (Ln = YIII 1, GdIII 2; hafc = hexafluoroacetylacetonate; NITPhOCH3 = 4′-methoxyo-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been investigated by density functional theory (DFT).
The magnetic coupling mechanisms were also explored from the viewpoint of molecular orbital and spin density populations.
DFT calculations show that the empty 4d-orbitals of YIII and 5d-orbitals of GdIII play an important role in the antiferromagnetic coupling between the two nitronyl nitroxide radical ligands, and that the
ferromagnetic coupling between the GdIII ion and the radical magnetic centers can be attributed to the nearly complete localization of the isotropic 4f-shell and singly occupied magnetic orbital (Π*) of the nitronyl nitroxide. 相似文献
8.
Hiroki Akiba Jun Sumaoka Dr. Makoto Komiyama Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(17):5018-5025
By using the luminescence from binuclear complexes of TbIII ( Tb2‐L1 and Tb2‐L2 ), phosphorylated Tyr residue in peptides was selectively detected in neutral aqueous solutions. Neither the non‐phosphorylated Tyr, pSer, pThr, nor the other phosphate‐containing biomolecules tested affected the luminescence intensity to any notable extent. Upon the binding of the pTyr to these TbIII complexes, the luminescence from the metal ion was notably promoted, as the light energy absorbed by the benzene ring of pTyr is efficiently transferred to the TbIII center. The binding activity of the binuclear TbIII complexes towards pTyr is two orders of magnitude larger than that of the corresponding mononuclear complex. These binuclear complexes were successfully used for real‐time monitoring of enzymatic phosphorylation of a peptide by a tyrosine kinase. 相似文献
9.
Nobuhiko Iki Dr. Munehiro Ohta Takayuki Horiuchi Dr. Hitoshi Hoshino Prof. 《化学:亚洲杂志》2008,3(5):849-853
The compositions and photophysical properties of luminescent ternary complexes of thiacalix[4]arene‐p‐sulfonate (TCAS), TbIII, and AgI ions were determined. At pH 6, AgI2?TbIII2?TCAS2 formed. Moreover, at pH 10, in the presence of a 20‐fold excess of AgI and a 50‐fold excess of TCAS with respect to TbIII, AgI2?TbIII?TCAS2 formed as the main luminescent species. The structure of these complexes was proposed: two TCAS ligands are linked by two S–AgI–S linkages to adopt a double‐cone supramolecular structure. Furthermore, each TbIII ion in the former complex accepts O?, S, O? donation, whereas in the latter, the TbIII center accepts eightfold O? donation. The luminescence quantum yield (Φ) of AgI2?TbIII2?TCAS2 (0.16) was almost equal to that of TbIII?TCAS, but the luminescence lifetime τ of the former (=1.09 ms) was larger than that of the latter. For AgI2?TbIII?TCAS2, the yield Φ (=0.11) was small, which is attributed to the low efficiency of photosensitization (η=0.11). However, the τ value (4.61 ms) was exceptionally large and almost equal to the natural luminescence lifetime of TbIII (4.7 ms), which is due to the absence of coordinating water molecules (q=0.1). This is compatible with the proposed structure in which the TbIII ion is shielded by a supramolecular cage that expels coordinated water molecules responsible for luminescence quenching. 相似文献
10.
Nadine Leygue Aritz Perez e Iñiguez De Heredia Chantal Galaup Eric Benoist Laurent Lamarque Claude Picard 《Tetrahedron》2018,74(31):4272-4287
A series of four new 18-membered hexaaza macrocyclic ligands bearing three endocyclic pyridine units and acetate or methylenephosphonate pendant arms has been prepared. The new synthetic procedure is based on the use of amine and diamine precursors incorporating masked carboxylate or phosphonate functions and on an efficient sodium template effect which controls the crucial macrocyclization step (yields of macrocyclization reactions: 62–88%). This procedure appears as a suitable alternative compared to the classical Richman-Atkins methodology generally used for the preparation of this class of macrocycles. As demonstrated with the EuIII and TbIII complexes derived from two ligands, these tripyridinophane chelators form luminescent and stable mononuclear LnIII complexes in aqueous solution at physiological pH. In such a medium, TbIII complexes exhibit a brightness of 1700 (λexc?=?279?nm) and 3000 (λexc?=?268?nm)?M?1?cm?1. 相似文献
11.
Daniel N. Huh Sierra R. Ciccone Samuel Bekoe Saswata Roy Joseph W. Ziller Prof. Filipp Furche Prof. William J. Evans 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16275-16280
Lanthanide triflates have been used to incorporate NdIII and SmIII ions into the 2.2.2-cryptand ligand (crypt) to explore their reductive chemistry. The Ln(OTf)3 complexes (Ln=Nd, Sm; OTf=SO3CF3) react with crypt in THF to form the THF-soluble complexes [LnIII(crypt)(OTf)2][OTf] with two triflates bound to the metal encapsulated in the crypt. Reduction of these LnIII-in-crypt complexes using KC8 in THF forms the neutral LnII-in-crypt triflate complexes [LnII(crypt)(OTf)2]. DFT calculations on [NdII(crypt)]2+], the first NdII cryptand complex, assign a 4f4 electron configuration to this ion. 相似文献
12.
Six‐Coordinate Lanthanide Complexes: Slow Relaxation of Magnetization in the Dysprosium(III) Complex
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Dr. Bo Na Xue‐Jing Zhang Prof. Dr. Wei Shi Prof. Dr. Yi‐Quan Zhang Prof. Dr. Bing‐Wu Wang Chen Gao Prof. Dr. Song Gao Prof. Dr. Peng Cheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(48):15975-15980
A series of six‐coordinate lanthanide complexes {(H3O)[Ln(NA)2]?H2O}n (H2NA=5‐hydroxynicotinic acid; Ln=GdIII ( 1?Gd ); TbIII ( 2?Tb ); DyIII ( 3?Dy ); HoIII ( 4?Ho )) have been synthesized from aqueous solution and fully characterized. Slow relaxation of the magnetization was observed in 3?Dy . To suppress the quantum tunneling of the magnetization, 3?Dy diluted by diamagnetic YIII ions was also synthesized and magnetically studied. Interesting butterfly‐like hysteresis loops and an enhanced energy barrier for the slow relaxation of magnetization were observed in diluted 3?Dy . The energy barrier (Δτ) and pre‐exponential factor (τ0) of the diluted 3?Dy are 75 K and 4.21×10?5 s, respectively. This work illustrates a successful way to obtain low‐coordination‐number lanthanide complexes by a framework approach to show single‐ion‐magnet‐like behavior. 相似文献
13.
Dr. Junhao Wang Jakub J. Zakrzewski Mikolaj Zychowicz Yue Xin Prof. Hiroko Tokoro Dr. Szymon Chorazy Prof. Shin-ichi Ohkoshi 《Angewandte Chemie (International ed. in English)》2023,62(35):e202306372
A conjunction of Single-Molecule Magnet (SMM) behavior and luminescence thermometry is an emerging research line aiming at contactless read-out of temperature in future SMM-based devices. The shared working range between slow magnetic relaxation and the thermometric response is typically narrow or absent. We report TbIII-based emissive SMMs formed in a cyanido-bridged framework whose properties are governed by the reversible structural transformation from [TbIII(H2O)2][CoIII(CN)6] ⋅ 2.7H2O ( 1 ) to its dehydrated phase, TbIII[CoIII(CN)6] ( 2 ). The 8-coordinated complexes in 1 show the moderate SMM effect but it is enhanced for trigonal-prismatic TbIII complexes in 2 , showing the SMM features up to 42 K. They are governed by the combination of QTM, Raman, and Orbach relaxation with the energy barrier of 594(18) cm−1 (854(26) K), one of the highest among the TbIII-based molecular nanomagnets. Both systems exhibit emission related to the f–f electronic transitions, with the temperature variations resulting in the optical thermometry below 100 K. The dehydration leads to a wide temperature overlap between the SMM behavior and thermometry, from 6 K to 42 K. These functionalities are further enriched after the magnetic dilution. The role of post-synthetic formation of high-symmetry TbIII complexes in achieving the SMM effect and hot-bands-based optical thermometry is discussed. 相似文献
14.
Daniel N. Huh Sierra R. Ciccone Samuel Bekoe Saswata Roy Joseph W. Ziller Filipp Furche William J. Evans 《Angewandte Chemie (International ed. in English)》2020,59(37):16141-16146
Lanthanide triflates have been used to incorporate NdIII and SmIII ions into the 2.2.2‐cryptand ligand (crypt) to explore their reductive chemistry. The Ln(OTf)3 complexes (Ln=Nd, Sm; OTf=SO3CF3) react with crypt in THF to form the THF‐soluble complexes [LnIII(crypt)(OTf)2][OTf] with two triflates bound to the metal encapsulated in the crypt. Reduction of these LnIII‐in‐crypt complexes using KC8 in THF forms the neutral LnII‐in‐crypt triflate complexes [LnII(crypt)(OTf)2]. DFT calculations on [NdII(crypt)]2+], the first NdII cryptand complex, assign a 4f4 electron configuration to this ion. 相似文献
15.
Exchange coupling and magnetic anisotropy in a family of bipyrimidyl radical‐bridged dilanthanide complexes: Density functional theory and ab initio calculations
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The origin of the magnetic anisotropy energy barriers in a series of bpym? (bpym = 2,2′‐bipyrimidine) radical‐bridged dilanthanide complexes [(Cp*2Ln)2(μ‐bpym)]+ [Cp* = pentamethylcyclopentadienyl; Ln = GdIII ( 1 ), TbIII ( 2 ), DyIII ( 3 ), HoIII ( 4 ), ErIII ( 5 )] has been explored using density functional theory (DFT) and ab initio methods. DFT calculations show that the exchange coupling between the two lanthanide ions for each complex is very weak, but the antiferromagnetic Ln‐bpym? couplings are strong. Ab initio calculations show that the effective energy barrier of 2 or 3 mainly comes from the contribution of a single TbIII or DyIII fragment, which is only about one third of a single Ln energy barrier. For 4 or 5 , however, both of the two HoIII or ErIII fragments contribute to the total energy barrier. Thus, it is insufficient to only increase the magnetic anisotropy energy barrier of a single Ln ion, while enhancing the Ln‐bpym? couplings is also very important. © 2014 Wiley Periodicals, Inc. 相似文献
16.
Summary
N-benzoylglycine hydrazide (BzGH) reacts with trivalent lanthanide metal ions forming complexes of the type [Ln(BzGH)2Cl(H2O)2]Cl2·nH2O, where Ln=LaIII, PrIII, NdIII, SmIII, EuIII, GdIII, TbIII, DyIII, or YIII;n=1 or 2. The structures of the complexes have been studied by conductance, magnetic, electronic, i.r.,1H n.m.r. and13C n.m.r. spectral techniques. The nephelauxetic ratio, the bonding parameter, Sinha's parameter and the covalency angular overlap parameter have been calculated from the electronic spectra of PrIII, NdIII and SmIII complexes. Seven-coordination is proposed in the NdIII complex. The i.r. and1H n.m.r. spectral data suggest bidentate BzGH in all the complexes. 相似文献
17.
Yin‐Shan Meng Yu‐Sen Qiao Prof. Dr. Yi‐Quan Zhang Dr. Shang‐Da Jiang Zhao‐Sha Meng Prof. Dr. Bing‐Wu Wang Prof. Dr. Zhe‐Ming Wang Prof. Dr. Song Gao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4704-4708
In recent years, plentiful lanthanide‐based (TbIII, DyIII, and ErIII) single‐molecule magnets (SMMs) were studied, while examples of other lanthanides, for example, TmIII are still unknown. Herein, for the first time, we show that by rationally manipulating the coordination sphere, two thulium compounds, 1 [(Tp)Tm(COT)] and 2 [(Tp*)Tm(COT)] (Tp=hydrotris(1‐pyrazolyl)borate; COT=cyclooctatetraenide; Tp*=hydrotris(3,5‐dimethyl‐1‐pyrazolyl)borate), can adopt the structure of non‐Kramers SMMs and exhibit their behaviors. Dynamic magnetic studies indicated that both compounds showed slow magnetic relaxation under dc field and a relatively high effective energy barrier (111 K for 1 , 46 K for 2 ). Magnetic diluted 1 a [(Tp)Tm0.05Y0.95(COT)] and 2 a [(Tp*)Tm0.05Y0.95(COT)] even exhibited magnetic relaxation under zero dc field. Relativistic ab initio calculations combined with single‐crystal angular‐resolved magnetometry measurements revealed the strong easy axis anisotropy and nearly degenerated ground doublet states. The comparison of 1 and 2 highlights the importance of local symmetry for obtaining Tm SMMs. 相似文献
18.
V. P. Kazakov A. I. Voloshin S. S. Ostakhov I. A. Khusainova 《Russian Chemical Bulletin》1996,45(10):2350-2354
Decomposition of dispiro(diadamantane-1,2-dioxetane) (1) in acetonitrile solutions of EuIII, GdIII, TbIII, PrIII, and CeIII perchlorates was studied by tile chemiluminescence method. The rate constants of decomposition of1 in complexes of composition1 · LnIII and stability constants of these complexes, as well as activation parameters of the decomposition of1 and thermodynamic parameters of the complexation were determined. A correlation between the thermodynamic parameters of complexation and ionic radii of LnIII was found.Translated fromIzvestiya Nauk. Seriya Khimicheskaya, No. 10, pp. 2479–2483, October, 1996. 相似文献
19.
Ju‐Wen Zhang Yi Man Yu‐Ning Ren Wen‐Hua Liu Bin‐Qiu Liu Yan‐Ping Dong 《无机化学与普通化学杂志》2019,645(6-7):580-587
The syntheses and crystal structures of eight lanthanide complexes with formula [Ln(2,5‐DCB)x(phen)y] are reported, which are characterized via single‐crystal, powder X‐ray diffraction, elemental analysis, IR spectroscopy, thermogravimetric analysis, photoluminescence measurement, and DC/AC magnetic measurement. These eight complexes are isostructural, and possess a discrete dinuclear structure. The adjacent dinuclear molecules are linked by the hydrogen bonding interactions into a one‐dimensional (1D) supramolecular chain. The neighboring 1D chains are further extended into a two‐dimensional (2D) supramolecular layer by the π–π stacking interactions. The photoluminescent properties of complexes 1 (NdIII), 2 (SmIII), 3 (EuIII), 5 (TbIII), 6 (DyIII), and 8 (YbIII) were investigated. Magnetic investigations also reveal the presence of ferromagnetic interactions in complexes 4 (GdIII), 6 (DyIII), and 7 (ErIII). Additionally, complex 6 (DyIII) demonstrates field‐induced slow magnetic relaxation behavior. 相似文献
20.
Dr. Fabrice Pointillart Dr. Thomas Cauchy Dr. Olivier Maury Yann Le Gal Dr. Stéphane Golhen Dr. Olivier Cador Dr. Lahcène Ouahab 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(39):11926-11941
The tetrathiafulvalene‐amido‐2‐pyridine‐N‐oxide ( L ) ligand has been employed to coordinate 4f elements. The architecture of the complexes mainly depends on the ionic radii of the lanthanides. Thus, the reaction of L in the same experimental protocol leads to three different molecular structure series. Binuclear [Ln2(hfac)5(O2CPhCl)( L )3] ? 2 H2O (hfac?=1,1,1,5,5,5‐hexafluoroacetylacetonate anion, O2CPhCl?=3‐chlorobenzoate anion) and mononuclear [Ln(hfac)3( L )2] complexes were obtained by using rare‐earth ions with either large (LnIII=Pr, Gd) or small (LnIII=Y, Yb) ionic radius, respectively, whereas the use of TbIII that possesses an intermediate ionic radius led to the formation of a binuclear complex of formula [Tb2(hfac)4(O2CPhCl)2( L )2]. Antiferromagnetic interactions have been observed in the three dinuclear compounds by using an extended empirical method. Photophysical properties of the coordination complexes have been studied by solid‐state absorption spectroscopy, whereas time‐dependent density functional theory (TD‐DFT) calculations have been carried out on the diamagnetic YIII derivative to build a molecular orbital diagram and to reproduce the absorption spectrum. For the [Yb(hfac)3( L )2] complex, the excitation at 19 600 cm?1 of the HOMO→LUMO+1/LUMO+2 charge‐transfer transition induces both line‐shape emissions in the near‐IR spectral range assigned to the 2F5/2→2F7/2 (9860 cm?1) ytterbium‐centered transition and a residual charge‐transfer emission around 13 150 cm?1. An efficient antenna effect that proceeds through energy transfer from the singlet excited state of the tetrathiafulvalene‐amido‐2‐pyridine‐N‐oxide chromophore is evidence of the YbIII sensitization. 相似文献