scholarly journals Trinuclear NiII-LnIII-NiII Complexes with Schiff Base Ligands: Synthesis, Structure, and Magnetic Properties

Molecules ◽  
2020 ◽  
Vol 25 (10) ◽  
pp. 2280 ◽  
Author(s):  
Anastasia N. Georgopoulou ◽  
Michael Pissas ◽  
Vassilis Psycharis ◽  
Yiannis Sanakis ◽  
Catherine P. Raptopoulou
Keyword(s):  
Magnetic Properties ◽  
Schiff Base ◽  
Lattice Structure ◽  
Schiff Base Ligands ◽  
Distorted Octahedral ◽  
Ferromagnetic Nature ◽  
Bidentate Chelate ◽  
Trinuclear Clusters ◽  
Best Fit ◽  
Oxygen Atoms

The reaction of the Schiff base ligand o-OH-C6H4-CH=N-C(CH2OH)3, H4L, with Ni(O2CMe)2∙4H2O and lanthanide nitrate salts in a 4 : 2 : 1 ratio lead to the formation of the trinuclear complexes [Ni2Ln(H3L)4(O2CMe)2](NO3) (Ln = Sm (1), Eu (2), Gd (3), Tb (4)). The complex cations contain the strictly linear NiII-LnIII-NiII moiety. The central LnIII ion is bridged to each of the terminal NiII ions through two deprotonated phenolato groups from two different ligands. Each terminal NiII ion is bound to two ligands in distorted octahedral N2O4 environment. The central lanthanide ion is coordinated to four phenolato oxygen atoms from the four ligands, and four carboxylato oxygen atoms from two acetates which are bound in the bidentate chelate mode. The lattice structure of complex 4 consists of two interpenetrating, supramolecular diamond like lattices formed through hydrogen bonds among neighboring trinuclear clusters. The magnetic properties of 1-4 were studied. For 3 the best fit of the magnetic susceptibility and isothermal M(H) data gave JNiGd = +0.42 cm−1, D = +2.95 cm−1 with gNi = gGd = 1.98. The ferromagnetic nature of the intramolecular Ni···Gd interaction revealed ground state of total spin S = 11/2. The magnetocaloric effect (MCE) parameters for 3 show that the change of the magnetic entropy (−ΔSm) reaches a maximum of 14.2 J kg−1 K−1 at 2 K. A brief literature survey of complexes containing the NiII-LnIII-NiII moiety is discussed in terms of their structural properties.

scholarly journals Synthesis, Crystal Structures and Magnetic Properties of Trinuclear {Ni2Ln} (LnIII = Dy, Ho) and {Ni2Y} Complexes with Schiff Base Ligands

Crystals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 95
Author(s):  
Despina Dermitzaki ◽  
Angeliki Panagiotopoulou ◽  
Michael Pissas ◽  
Yiannis Sanakis ◽  
Vassilis Psycharis ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Schiff Base ◽  
Complex Cation ◽  
Schiff Base Ligands ◽  
Linear Arrangement ◽  
Lanthanide Nitrate ◽  
Trinuclear Complexes ◽  
Distorted Octahedral ◽  
Bidentate Chelate ◽  
Slow Magnetic Relaxation

The reaction of the Schiff base ligand o-OH-C6H4-CH=N-C(CH2OH)3, H4L, with Ni(O2CMe)2∙4H2O and lanthanide nitrate salts in a 4:2:1 ratio lead to the formation of the trinuclear complexes [Ni2Ln(H3L)4(O2CMe)2](NO3) (Ln = Dy (1), Ho (2), and Y (3)) which crystallize in the non-centrosymmetric space group Pna21. The complex cation consists of the three metal ions in an almost linear arrangement. The {Ni2Ln} moieties are bridged through two deprotonated Ophenolato groups from two different ligands. Each terminal NiII ion is bound to two ligands through their Ophenolato, the Nimino atoms and one of the protonated Oalkoxo groups in a distorted octahedral. The central lanthanide ion is coordinated to four Ophenolato oxygen from the four ligands, and four Ocarboxylato atoms from two acetates which are bound in the bidentate chelate mode, and the coordination polyhedron is biaugmented trigonal prism, which probably results in a non-centrosymmetric arrangement of the complexes in the lattice. The magnetic properties of 1–3 were studied and showed that 1 exhibits field induced slow magnetic relaxation.

Crystal Structure and Magnetic Properties of a New Hetero-Dinuclear CuIIMnII Schiff Base Complex

2003 ◽  
Vol 58 (4) ◽  
pp. 271-277 ◽  
Author(s):  
Y. Elerman ◽  
A. Elmali ◽  
C. T. Zeyrek ◽  
I. Svoboda ◽  
H. Fuess
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Schiff Base ◽  
Schiff Base Complex ◽  
Antiferromagnetic Interaction ◽  
Monoclinic Space Group ◽  
Distorted Tetrahedron ◽  
Molar Magnetic Susceptibility ◽  
Schiff Base Ligands ◽  
Oxygen Atoms

Mn[Cu(L)(O2CMe)2] · H2O (L = N,N’-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane) was synthesized and the crystal structure determined. (C23H26CuMnN2O8).H2O, monoclinic, space group P21/c, a = 12.017(3), b = 8.217(3), c = 24.786(4) Å , β = 92.10(2)°, V = 2446(1) Å3, Z = 4. The crystal structure consists of ordered dinuclear units with CuII and MnII ions bridged by two oxygen atoms of the Schiff base ligand. The CuII coordination sphere is a slightly distorted square-plane formed by the N2O2 donor set of the Schiff base ligands. The average Cu-O and Cu-N distances are 1.920(1) and 1.957(4) Å , respectively. The coordination around the MnII ion is a distorted tetrahedron with the donor oxygen atoms of the Schiff base ligands and oxygen atoms of the acetate anions. The Cu ··· Mn separation is 3.327(4) Å . There is also one non-coordinating water molecule in the crystal structure. The χ and χT versus T plots, χ being the molar magnetic susceptibility per CuIIMnII unit and T the temperature, has been measured in the 4.9 - 301 K temperature range. The values of the interaction parameters are J = −28.3 cm−1, gMn = 2.01, gCu = 2.07. This indicates an intramolecular antiferromagnetic interaction between CuII and MnII ions.

Crystal Structures of Heteronuclear Nickel(II)/Zinc(II) Doubly Oxygen Bridged Schiff-Base Complexes

2003 ◽  
Vol 58 (6) ◽  
pp. 539-542 ◽  
Author(s):  
Ayhan Elmali ◽  
Yalçın Elerman
Keyword(s):  
Schiff Base ◽  
Crystal Structures ◽  
Octahedral Geometry ◽  
Schiff Base Complexes ◽  
Distorted Octahedral Geometry ◽  
Schiff Base Ligands ◽  
Distorted Octahedral ◽  
Oxygen Atoms

{[μ-Bis(5-chlorosalicylidene)-1,3-propanediaminato]nickel(II)}dichlorozinc(II) ·2 dmf (dmf = dimethylformamide) 1 and {[μ-bis(5-bromosalicylidene)-1,3- propanediaminato]nickel(II)}- dichlorozinc(II) ·2 dmf (dmf) 2 were synthesized and their crystal structures determined. In both structures, the Ni(II) ions have a distorted octahedral geometry involving the N2O2 atoms of the Schiff-base ligands and two oxygen atoms of dimethylformamide (dmf) molecules. The coordination around the Zn(II) ions is distorted tetrahedral. The Ni···Zn distances are 3.132(1) Å for 1 and 3.122(1) Å for 2.

Synthesis, Structure and Fluorescence Properties of a Trinuclear Zn(II) Complex with N,N,O-donor Schiff Base Ligands and Bridging Acetates

2009 ◽  
Vol 64 (4) ◽  
pp. 403-408 ◽  
Author(s):  
Shyamapada Shit ◽  
Joy Chakraborty ◽  
Brajagopal Samanta ◽  
Georgina M. Rosair ◽  
Samiran Mitra
Keyword(s):  
Schiff Base ◽  
Schiff Base Ligand ◽  
Fluorescence Properties ◽  
Schiff Base Ligands ◽  
Thermal Methods ◽  
Metal Centers ◽  
X Ray ◽  
Octahedral Environment ◽  
Distorted Octahedral ◽  
Ft Ir

A new centrosymmetric trinuclear Zn(II) complex [Zn3L2(CH3COO)4] (1) has been synthesized by the reaction of Zn(CH3COO)2 · 2H2O with a tridentate N,N,O-donor Schiff base ligand HL [C5H4NC(CH3)=NC6H4(OH)] and systematically characterized by elemental analysis, FT-IR, UV/Vis and thermal methods. Single crystal X-ray structure analysis reveals that three Zn(II) centers are in two different coordination environments. Two terminal Zn(II) centers adopt a distorted squarepyramidal geometry leaving the central Zn(II) in a distorted octahedral environment. Two adjacent metal centers are connected through single μ2-phenolato as well as double μ-acetato-O,O´ syn-syn bridges. Fluorescence properties of the complex as compared to the ligand indicate that the former can serve as a potential photoactive material.

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