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Crystal Structures of Metal Complexes

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Inorganic Chemistry".

Deadline for manuscript submissions: closed (31 May 2022) | Viewed by 20528

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Special Issue Editor

Department of Science, Faculty of Science, Yamagata University, Kojirakawa, Yamagata 990-8560, Japan
Interests: coordination compounds; spin-orbit coupling; structural prediction; ligand field theory; machine learning

Special Issue Information

Dear Colleagues,

Welcome to the Special Issue, "Crystal Structures of Metal Complexes".

We would like to invite you, the authors, to submit any contributions on crystal structures of metal complexes. New crystal structures are always fascinating, and structural prediction studies on previous crystal structures are also important.

Crystal structures are very interesting in many aspects, including symmetry and distortion of coordination polyhedron in mononuclear complexes, variety of homo and hetero d multinuclear metal complexes, beautiful network structure of polymeric metal organic framework compounds.

Discussing the relationship between crystal structures and some physicochemical properties are, of course, welcome. Magnetic data, spectral data, and so on, are often theoretically related with the structures. Some crystal structures are difficult to be determined due to disorder and so on. Report on such crystal structures is valuable. Phase transition phenomena and soft-crystal behavior are also intriguing. Investigation on intramolecular and intermolecular interaction and studies on crystal-growing mechanisms are also enthusiastically welcomed.

We look forward to your contribution.

Prof. Dr. Hiroshi Sakiyama
Guest Editor

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Keywords

  • crystal structure
  • metal complex
  • discrete complex
  • metal organic framework
  • physicochemical properties
  • symmetry
  • interaction
  • structural prediction

Published Papers (11 papers)

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15 pages, 4811 KiB  
Article
Speciation of Tellurium(VI) in Aqueous Solutions: Identification of Trinuclear Tellurates by 17O, 123Te, and 125Te NMR Spectroscopy
by Alexander G. Medvedev, Oleg Yu. Savelyev, Dmitry P. Krut’ko, Alexey A. Mikhaylov, Ovadia Lev and Petr V. Prikhodchenko
Molecules 2022, 27(24), 8654; https://doi.org/10.3390/molecules27248654 - 07 Dec 2022
Viewed by 1139
Abstract
Tellurates have attracted the attention of researchers over the past decade due to their properties and as less toxic forms of tellurium derivatives. However, the speciation of Te(VI) in aqueous solutions has not been comprehensively studied. We present a study of the equilibrium [...] Read more.
Tellurates have attracted the attention of researchers over the past decade due to their properties and as less toxic forms of tellurium derivatives. However, the speciation of Te(VI) in aqueous solutions has not been comprehensively studied. We present a study of the equilibrium speciation of tellurates in aqueous solutions at a wide pH range, 2.5–15 by 17O, 123Te, and 125Te NMR spectroscopy. The coexistence of monomeric, dimeric, and trimeric oxidotellurate species in chemical equilibrium at a wide pH range has been shown. NMR spectroscopy, DFT computations, and single-crystal X-ray diffraction studies confirmed the formation and coexistence of trimeric tellurate anions with linear and triangular structures. Two cesium tellurates, Cs2[Te4O8(OH)10] and Cs2[Te2O4(OH)6], were isolated from the solution at pH 5.5 and 9.2, respectively, and studied by single-crystal X-ray diffractometry, revealing dimeric and tetrameric tellurate anions in corresponding crystal structures. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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14 pages, 3390 KiB  
Article
Synthesis and Characterization of Lanthanide Metal Ion Complexes of New Polydentate Hydrazone Schiff Base Ligand
by Izabela Pospieszna-Markiewicz, Marta A. Fik-Jaskółka, Zbigniew Hnatejko, Violetta Patroniak and Maciej Kubicki
Molecules 2022, 27(23), 8390; https://doi.org/10.3390/molecules27238390 - 01 Dec 2022
Cited by 4 | Viewed by 1948
Abstract
The new homodinuclear complexes of the general formula [Ln2L3(NO3)3] (where HL is newly synthesized 2-((2-(benzoxazol-2-yl)-2-methylhydrazono)methyl)phenol and Ln = Sm3+ (1), Eu3+ (2), Tb3+ (3a, 3b), [...] Read more.
The new homodinuclear complexes of the general formula [Ln2L3(NO3)3] (where HL is newly synthesized 2-((2-(benzoxazol-2-yl)-2-methylhydrazono)methyl)phenol and Ln = Sm3+ (1), Eu3+ (2), Tb3+ (3a, 3b), Dy3+ (4), Ho3+ (5), Er3+ (6), Tm3+ (7), Yb3+ (8)), have been synthesized from the lanthanide(III) nitrates with the polydentate hydrazone Schiff base ligand. The flexibility of this unsymmetrical Schiff base ligand containing N2O binding moiety, attractive for lanthanide metal ions, allowed for a self-assembly of these complexes. The compounds were characterized by spectroscopic data (ESI-MS, IR, UV/Vis, luminescence) and by the X-ray structure determination of the single crystals, all of which appeared to be different solvents. The analytical data suggested 2:3 metal:ligand stoichiometry in these complexes, and this was further confirmed by the structural results. The metal cations are nine-coordinated, by nitrogen and oxygen donor atoms. The complexes are two-centered, with three oxygen atoms in bridging positions. There are two types of structures, differing by the sources of terminal (non-bridging) coordination centers (group A: two ligands, one nitro anion/one ligand, two nitro anions, group B: three ligands, three anions). Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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9 pages, 2139 KiB  
Article
Selective Formation of Unsymmetric Multidentate Azine-Based Ligands in Nickel(II) Complexes
by Kennedy Mawunya Hayibor, Yukinari Sunatsuki and Takayoshi Suzuki
Molecules 2022, 27(20), 6788; https://doi.org/10.3390/molecules27206788 - 11 Oct 2022
Cited by 3 | Viewed by 1201
Abstract
A mixture of 2-pyridine carboxaldehyde, 4-formylimidazole (or 2-methyl-4-formylimidazole), and NiCl2·6H2O in a molar ratio of 2:2:1 was reacted with two equivalents of hydrazine monohydrate in methanol, followed by the addition of aqueous NH4PF6 solution, afforded a [...] Read more.
A mixture of 2-pyridine carboxaldehyde, 4-formylimidazole (or 2-methyl-4-formylimidazole), and NiCl2·6H2O in a molar ratio of 2:2:1 was reacted with two equivalents of hydrazine monohydrate in methanol, followed by the addition of aqueous NH4PF6 solution, afforded a NiII complex with two unsymmetric azine-based ligands, [Ni(HLH)2](PF6)2 (1) or [Ni(HLMe)2](PF6)2 (2), in a high yield, where HLH denotes 2-pyridylmethylidenehydrazono-(4-imidazolyl)methane and HLMe is its 2-methyl-4-imidazolyl derivative. The spectroscopic measurements and elemental analysis confirmed the phase purity of the bulk products, and the single-crystal X-ray analysis revealed the molecular and crystal structures of the NiII complexes bearing an unsymmetric HLH or HLMe azines in a tridentate κ3N, N’, N” coordination mode. The HLH complex with a methanol solvent, 1·MeOH, crystallizes in the orthorhombic non-centrosymmetric space group P212121 with Z = 4, affording conglomerate crystals, while the HLMe complex, 2·H2O·Et2O, crystallizes in the monoclinic and centrosymmetric space group P21/n with Z = 4. In the crystal of 2·H2O·Et2O, there is intermolecular hydrogen-bonding interaction between the imidazole N–H and the neighboring uncoordinated azine-N atom, forming a one-dimensional polymeric structure, but there is no obvious magnetic interaction among the intra- and interchain paramagnetic NiII ions. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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14 pages, 3210 KiB  
Article
Mixed-Valent Trinuclear CoIII-CoII-CoIII Complex with 1,3-Bis(5-chlorosalicylideneamino)-2-propanol
by Masahiro Mikuriya, Yuko Naka, Ayumi Inaoka, Mika Okayama, Daisuke Yoshioka, Hiroshi Sakiyama, Makoto Handa and Motohiro Tsuboi
Molecules 2022, 27(13), 4211; https://doi.org/10.3390/molecules27134211 - 30 Jun 2022
Cited by 2 | Viewed by 1053
Abstract
A mixed-valent trinuclear complex with 1,3-bis(5-chlorosalicylideneamino)-2-propanol (H3clsalpr) was synthesized, and the crystal structure was determined by the single-crystal X-ray diffraction method at 90 K. The molecule is a trinuclear CoIII-CoII-CoIII complex with octahedral geometries, having a [...] Read more.
A mixed-valent trinuclear complex with 1,3-bis(5-chlorosalicylideneamino)-2-propanol (H3clsalpr) was synthesized, and the crystal structure was determined by the single-crystal X-ray diffraction method at 90 K. The molecule is a trinuclear CoIII-CoII-CoIII complex with octahedral geometries, having a tetradentate chelate of the Schiff-base ligand, bridging acetate, monodentate acetate coordination to each terminal Co3+ ion and four bridging phenoxido-oxygen of two Schiff-base ligands, and two bridging acetate-oxygen atoms for the central Co2+ ion. The electronic spectral feature is consistent with the mixed valent CoIII-CoII-CoIII. Variable-temperature magnetic susceptibility data could be analyzed by consideration of the axial distortion of the central Co2+ ion with the parameters Δ = –254 cm−1, λ = –58 cm−1, κ = 0.93, tip = 0.00436 cm3 mol−1, θ = –0.469 K, gz = 6.90, and gx = 2.64, in accordance with a large anisotropy. The cyclic voltammogram showed an irreversible reduction wave at approximately −1.2 V·vs. Fc/Fc+, assignable to the reduction of the terminal Co3+ ions. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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14 pages, 2334 KiB  
Article
Fluorescent Zn(II)-Based Metal-Organic Framework: Interaction with Organic Solvents and CO2 and Methane Capture
by Sifani Zavahir, Hamdi Ben Yahia, Julian Schneider, DongSuk Han, Igor Krupa, Tausif Altamash, Mert Atilhan, Abdulkarem Amhamed and Peter Kasak
Molecules 2022, 27(12), 3845; https://doi.org/10.3390/molecules27123845 - 15 Jun 2022
Cited by 4 | Viewed by 1898
Abstract
Adsorption of carbon dioxide (CO2), as well as many other kinds of small molecules, is of importance for industrial and sensing applications. Metal-organic framework (MOF)-based adsorbents are spotlighted for such applications. An essential for MOF adsorbent application is a simple and [...] Read more.
Adsorption of carbon dioxide (CO2), as well as many other kinds of small molecules, is of importance for industrial and sensing applications. Metal-organic framework (MOF)-based adsorbents are spotlighted for such applications. An essential for MOF adsorbent application is a simple and easy fabrication process, preferably from a cheap, sustainable, and environmentally friendly ligand. Herein, we fabricated a novel structural, thermally stable MOF with fluorescence properties, namely Zn [5-oxo-2,3-dihydro-5H-[1,3]-thiazolo [3,2-a]pyridine-3,7-dicarboxylic acid (TPDCA)] • dimethylformamide (DMF) •0.25 H2O (coded as QUF-001 MOF), in solvothermal conditions by using zinc nitrate as a source of metal ion and TPDCA as a ligand easy accessible from citric acid and cysteine. Single crystal X-ray diffraction analysis and microscopic examination revealed the two-dimensional character of the formed MOF. Upon treatment of QUF-001 with organic solvents (such as methanol, isopropanol, chloroform, dimethylformamide, tetrahydrofuran, hexane), interactions were observed and changes in fluorescence maxima as well as in the powder diffraction patterns were noticed, indicating the inclusion and intercalation of the solvents into the interlamellar space of the crystal structure of QUF-001. Furthermore, CO2 and CH4 molecule sorption properties for QUF-001 reached up to 1.6 mmol/g and 8.1 mmol/g, respectively, at 298 K and a pressure of 50 bars. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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15 pages, 3240 KiB  
Article
Synthesis, Crystal Structure and Magnetic Properties of a Trinuclear Copper(II) Complex Based on P-Cresol-Substituted Bis(α-Nitronyl Nitroxide) Biradical
by Sabrina Grenda, Maxime Beau and Dominique Luneau
Molecules 2022, 27(10), 3218; https://doi.org/10.3390/molecules27103218 - 18 May 2022
Cited by 1 | Viewed by 2105
Abstract
Trinuclear copper(II) complex [CuII3(NIT2PhO)2Cl4] was synthesized with p-cresol-substituted bis(α-nitronyl nitroxide) biradical: 4-methyl-2,6-bis(1-oxyl-3-oxido-4,4,5,5-tetramethyl-2-imidazolin-2-yl)phenol (NIT2PhOH). The crystal structure of this heterospin complex was determined using single-crystal X-ray diffraction analysis and exhibits four unusual seven-membered [...] Read more.
Trinuclear copper(II) complex [CuII3(NIT2PhO)2Cl4] was synthesized with p-cresol-substituted bis(α-nitronyl nitroxide) biradical: 4-methyl-2,6-bis(1-oxyl-3-oxido-4,4,5,5-tetramethyl-2-imidazolin-2-yl)phenol (NIT2PhOH). The crystal structure of this heterospin complex was determined using single-crystal X-ray diffraction analysis and exhibits four unusual seven-membered metallocycles formed from the coordination of oxygen atoms of the N-O groups and of bridging phenoxo (µ-PhO) moieties with copper(II) ions. The crystal structure analysis reveals an incipient agostic interaction between a square planar copper center and a hydrogen-carbon bond from one methyl group carried on the coordinated nitronyl-nitroxide radical. The intramolecular Cu∙∙∙H-C interaction involves a six-membered metallocycle and may stabilize the copper center in square planar coordination mode. From the magnetic susceptibility measurements, the complex, which totals seven S = 1/2 spin carriers, has almost a ground state spin S = 1/2 at room temperature ascribed to strong antiferromagnetic interaction between the nitronyl nitroxide moieties and the copper(II) centers and in between the copper(II) centers through the bridging phenoxo oxygen atom. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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13 pages, 2299 KiB  
Article
Selective Formation of Intramolecular Hydrogen-Bonding Palladium(II) Complexes with Nucleosides Using Unsymmetrical Tridentate Ligands
by Ryoji Mitsuhashi, Yuya Imai, Takayoshi Suzuki and Yoshihito Hayashi
Molecules 2022, 27(7), 2098; https://doi.org/10.3390/molecules27072098 - 24 Mar 2022
Cited by 1 | Viewed by 1680
Abstract
Three palladium(II) complexes with amino-amidato-phenolato-type tridentate ligands were synthesized and characterized by 1H NMR spectroscopy and X-ray crystallography. The strategic arrangement of a hydrogen-bond donor and acceptor adjacent to the substitution site of the PdII complex allowed the selective coordination of [...] Read more.
Three palladium(II) complexes with amino-amidato-phenolato-type tridentate ligands were synthesized and characterized by 1H NMR spectroscopy and X-ray crystallography. The strategic arrangement of a hydrogen-bond donor and acceptor adjacent to the substitution site of the PdII complex allowed the selective coordination of nucleosides. Among two pyrimidine-nucleosides, cytidine and 5-methyluridine, cytidine was successfully coordinated to the PdII complex while 5-methyluridne was not. On the other hand, both purine-nucleosides, adenosine and guanosine, were coordinated to the PdII complex. As purines have several coordination sites, adenosine afforded three kinds of coordination isomers expected from the three different donors. However, guanosine afforded a sole product according to the ligand design such that the formation of double intramolecular hydrogen-bond strongly induced the specific coordination by N1-position of guanine moiety. Furthermore, the preference of the nucleosides was evaluated by scrambling reactions. It was found that the preference of guanosine is nearly twice as high as adenosine and cytidine, owing to the three-point interaction of a coordination bond and two hydrogen bonds. These results show that the combination of a coordination and hydrogen bonds, which is reminiscent of the Watson–Crick base pairing, is an effective tool for the precise recognition of nucleosides. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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12 pages, 3404 KiB  
Article
A New Pt(II) Complex with Anionic s-Triazine Based NNO-Donor Ligand: Synthesis, X-ray Structure, Hirshfeld Analysis and DFT Studies
by Mezna Saleh Altowyan, Saied M. Soliman, Jamal Lasri, Naser E. Eltayeb, Matti Haukka, Assem Barakat and Ayman El-Faham
Molecules 2022, 27(5), 1628; https://doi.org/10.3390/molecules27051628 - 01 Mar 2022
Cited by 4 | Viewed by 2362
Abstract
The reaction of PtCl2 with s-triazine-type ligand (HTriaz) (1:1) in acetone under heating afforded a new [Pt(Triaz)Cl] complex. Single-crystal X-ray diffraction analysis showed that the ligand (HTriaz) is an NNO tridentate chelate via two N-atoms from the [...] Read more.
The reaction of PtCl2 with s-triazine-type ligand (HTriaz) (1:1) in acetone under heating afforded a new [Pt(Triaz)Cl] complex. Single-crystal X-ray diffraction analysis showed that the ligand (HTriaz) is an NNO tridentate chelate via two N-atoms from the s-triazine and hydrazone moieties and one oxygen from the deprotonated phenolic OH. The coordination environment of the Pt(II) is completed by one Cl−1 ion trans to the Pt-N(hydrazone). Hirshfeld surface analysis showed that the most dominant interactions are the H···H, H···C and O···H intermolecular contacts. These interactions contributed by 60.9, 11.2 and 8.3% from the whole fingerprint area, respectively. Other minor contributions from the Cl···H, C···N, N···H and C···C contacts were also detected. Among these interactions, the most significant contacts are the O···H, H···C and H···H interactions. The amounts of the electron transfer from the ligand groups to Pt(II) metal center were predicted using NBO calculations. Additionally, the electronic spectra were assigned based on the TD-DFT calculations. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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15 pages, 4419 KiB  
Article
Magnetic and Luminescence Properties of 8-Coordinate Holmium(III) Complexes Containing 4,4,4-Trifluoro-1-Phenyl- and 1-(Naphthalen-2-yl)-1,3-Butanedionates
by Franz A. Mautner, Florian Bierbaumer, Ramon Vicente, Saskia Speed, Ánnia Tubau, Mercè Font-Bardía, Roland C. Fischer and Salah S. Massoud
Molecules 2022, 27(3), 1129; https://doi.org/10.3390/molecules27031129 - 08 Feb 2022
Cited by 3 | Viewed by 2296
Abstract
A new series of mononuclear Ho3+ complexes derived from the β-diketonate anions: 4,4,4-trifluoro-1-phenyl-1,3-butanedioneate (btfa) and 4,4,4-trifuoro-1-(naphthalen-2-yl)-1,3-butanedionate (ntfa) have been synthesized, [Ho(btfa)3(H2O)2] (1a), [Ho(ntfa)3(MeOH)2] (1b), [...] Read more.
A new series of mononuclear Ho3+ complexes derived from the β-diketonate anions: 4,4,4-trifluoro-1-phenyl-1,3-butanedioneate (btfa) and 4,4,4-trifuoro-1-(naphthalen-2-yl)-1,3-butanedionate (ntfa) have been synthesized, [Ho(btfa)3(H2O)2] (1a), [Ho(ntfa)3(MeOH)2] (1b), (1), [Ho(btfa)3(phen)] (2), [Ho(btfa)3(bipy)] (3), [Ho(btfa)3(di-tbubipy)] (4), [Ho(ntfa)3(Me2bipy)] (5), and [Ho(ntfa)3(bipy)] (6), where phen is 1,10-phenantroline, bipy is 2,2′-bipyridyl, di-tbubipy is 4,4′-di-tert-butyl-2,2′-bipyridyl, and Me2bipy is 4,4′-dimethyl-2,2′-bipyridyl. These compounds have been characterized by elemental microanalysis and infrared spectroscopy as well as single-crystal X-ray difraction for 26. The central Ho3+ ions in these compounds display coordination number 8. The luminescence-emission properties of the pyridyl adducts 26 display a strong characteristic band in the visible region at 661 nm and a series of bands in the NIR region (excitation wavelengths (λex) of 367 nm for 24 and 380 nm for 5 and 6). The magnetic properties of the complexes revealed magnetically uncoupled Ho3+ compounds with no field-induced, single-molecule magnet (SMMs). Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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14 pages, 2681 KiB  
Article
Structures of Dimer-of-Dimers Type Defect Cubane Tetranuclear Copper(II) Complexes with Novel Dinucleating Ligands
by Ryusei Hoshikawa, Ryoji Mitsuhashi, Eiji Asato, Jianqiang Liu and Hiroshi Sakiyama
Molecules 2022, 27(2), 576; https://doi.org/10.3390/molecules27020576 - 17 Jan 2022
Cited by 6 | Viewed by 2013
Abstract
Only a limited number of multinucleating ligands can stably maintain multinuclear metal structures in aqueous solutions. In this study, a water-soluble dinucleating ligand, 2,6-bis{[N-(carboxylatomethyl)-N-methyl-amino]methyl}-4-methylphenolate ((sym-cmp)3−), was prepared and its copper(II) complexes were structurally characterized. Using [...] Read more.
Only a limited number of multinucleating ligands can stably maintain multinuclear metal structures in aqueous solutions. In this study, a water-soluble dinucleating ligand, 2,6-bis{[N-(carboxylatomethyl)-N-methyl-amino]methyl}-4-methylphenolate ((sym-cmp)3−), was prepared and its copper(II) complexes were structurally characterized. Using the single-crystal X-ray diffraction method, their dimer-of-dimers type defect cubane tetranuclear copper(II) structures were characterized for [Cu4(sym-cmp)2Cl2(H2O)2] and [Cu4(sym-cmp)2(CH3O)2(CH3OH)2]. In the complexes, each copper(II) ion has a five-coordinate square-pyramidal coordination geometry. The coordination bond character was confirmed by the density functional theory (DFT) calculation on the basis of the crystal structure, whereby we found the bonding and anti-bonding molecular orbitals. From the cryomagnetic measurement and the magnetic analysis, overall antiferromagnetic interaction was observed, and this magnetic behavior is also explained by the DFT result. Judging from the molar conductance and the electronic spectra, the bridging chlorido ligand dissociates in water, but the dinuclear copper(II) structure was found to be maintained in an aqueous solution. In conclusion, the tetranuclear copper(II) structures were crystallographically characterized, and the dinuclear copper(II) structures were found to be stabilized even in an aqueous solution. Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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14 pages, 4374 KiB  
Viewpoint
Highlighting Recent Crystalline Engineering Aspects of Luminescent Coordination Polymers Based on F-Elements and Ditopic Aliphatic Ligands
by Richard F. D’Vries, Germán E. Gomez and Javier Ellena
Molecules 2022, 27(12), 3830; https://doi.org/10.3390/molecules27123830 - 14 Jun 2022
Cited by 2 | Viewed by 1587
Abstract
Three principal factors may influence the final structure of coordination polymers (CPs): (i) the nature of the ligand, (ii) the type and coordination number of the metal center, and (iii) the reaction conditions. Further, flexible carboxylate aliphatic ligands have been widely employed as [...] Read more.
Three principal factors may influence the final structure of coordination polymers (CPs): (i) the nature of the ligand, (ii) the type and coordination number of the metal center, and (iii) the reaction conditions. Further, flexible carboxylate aliphatic ligands have been widely employed as building blocks for designing and synthesizing CPs, resulting in a diverse array of materials with exciting architectures, porosities, dimensionalities, and topologies as well as an increasing number of properties and applications. These ligands show different structural features, such as torsion angles, carbon backbone number, and coordination modes, which affect the desired products and so enable the generation of polymorphs or crystalline phases. Additionally, due to their large coordination numbers, using 4f and 5f metals as coordination centers combined with aliphatic ligands increases the possibility of obtaining different crystal phases. Additionally, by varying the synthetic conditions, we may control the production of a specific solid phase by understanding the thermodynamic and kinetic factors that influence the self-assembly process. This revision highlights the relationship between the structural variety of CPs based on flexible carboxylate aliphatic ligands and f-elements (lanthanide and actinides) and their outstanding luminescent properties such as solid-state emissions, sensing, and photocatalysis. In this sense, we present a structural analysis of the CPs reported with the oxalate ligand, as the one rigid ligand of the family, and other flexible dicarboxylate linkers with –CH2– spacers. Additionally, the nature of the luminescence properties of the 4f or 5f-CPs is analyzed, and finally, we present a novel set of CPs using a glutarate-derived ligand and samarium, with the formula [2,2′-bipyH][Sm(HFG)2 (2,2′-bipy) (H2O)2]•(2,2′-bipy) (α-Sm) and [2,2′-bipyH][Sm(HFG)2 (2,2′-bipy) (H2O)2] (β-Sm). Full article
(This article belongs to the Special Issue Crystal Structures of Metal Complexes)
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