Three heterobinuclear complexes were synthesized, namely [Cu (oxpn) Co (L)2] (ClO4)2·xH2O(L= 2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen) , and 5-nitro-1, 10-phenanthroline (NO2-phen)), where oxpn represent...Three heterobinuclear complexes were synthesized, namely [Cu (oxpn) Co (L)2] (ClO4)2·xH2O(L= 2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen) , and 5-nitro-1, 10-phenanthroline (NO2-phen)), where oxpn represents N, N'-bis(3-aminopropyl) oxam-ido. Based on 1R, elemental analysis, conductivity measurement and electronic spectra, these complexes were characterized by an extended oxamido-bridged structure with Cu(Ⅱ) in a planar environment and Co(Ⅱ) in a octahedral environment. The symmetry of the cation is very close to C2v.The complexes were also characterized with variable temperature (4~300K) magnetic susceptibility, and the data were fit for the susceptibility equation derived from spin Hamilton, H= -2JS1.S2-DSx12 by least square strategy. The exchange integral, J, was found to be -22.36 cm-1 (for bpy);-15.45 cm-1 (for phen); -19. 10cm-1(for NO2-phen), indicating that there is a weak antiferromagnetic spin-exchange interaction between the metal ions.展开更多
The copper( Ⅱ ) complex, [Cu(oxpn)Cu(tmen)2](ClO4)2 was synthesized, where oxpn is N, N' -bis ( 3-aminopropyl) oxamido and tmen is N, N, N' N' -tetram-ethylethylenediamine. The crystal is triclinic, space...The copper( Ⅱ ) complex, [Cu(oxpn)Cu(tmen)2](ClO4)2 was synthesized, where oxpn is N, N' -bis ( 3-aminopropyl) oxamido and tmen is N, N, N' N' -tetram-ethylethylenediamine. The crystal is triclinic, space group P 1, a=1-2349(2), b = 1.3093(2), c=1. 3855(2) nm, α=61-88(1), β=69.49(1), γ=57.91(1)°? V = 1. 6589 nm3, Z = 2. Both copper( Ⅱ ) ions are in a square pyramidal coordination environment , and linked by oxamido bridge. The distance between them is 0. 526 nm. Variable temperature (4. 2-300 K) magnetic susceptibility data for this complex show that there exists a relatively large antiferromagnetic exchange interaction between the two copper( Ⅱ ) ions with a J value of-740. 40 cm-1.展开更多
Six novel μ-oxamido heterobinuclear complexes, namely Cu(oxae)Ln(Me2bpy)2-(ClO4)3 (Ln=La, Nd, Gd, Tb, Ho, Er), where oxae denotes N, N'-bis(2-aminoethyl)oxamido dian-ion, Me2bpy is 4,4'-dimethyl-2,2'-bipy...Six novel μ-oxamido heterobinuclear complexes, namely Cu(oxae)Ln(Me2bpy)2-(ClO4)3 (Ln=La, Nd, Gd, Tb, Ho, Er), where oxae denotes N, N'-bis(2-aminoethyl)oxamido dian-ion, Me2bpy is 4,4'-dimethyl-2,2'-bipyridyl, have been synthesized and characterized by elemental analyses, IR, conductivity measurements and electronic spectra. The temperature dependence of the magnetic susceptibility of Cu(oxae)Gd(Me2bpy)2(ClO4)3 has been meaured over the range 4-300 K. The least-squares fit of the experimental susceptibilities yielded J - 1.87 cm-1.The observed Gd(Ⅲ)-Cu(Ⅱ) coupling is ferromagnetic. One plausible mechanism that can cause a ferromagnetic coupling between Gd(Ⅲ) and Cu(Ⅱ) is discussed in terms of spin-polarization.展开更多
Three dinuclear complexes were synthesized and designated as Cu(obp)CuL where obp =oxamidobis(propionato), L=2,2' -bipyridyl(bpy) (1), 1 , 10-phenathroline(phen)(2) and 5-nitro-1, 10-phenathroline(NO2-phen)(3). Th...Three dinuclear complexes were synthesized and designated as Cu(obp)CuL where obp =oxamidobis(propionato), L=2,2' -bipyridyl(bpy) (1), 1 , 10-phenathroline(phen)(2) and 5-nitro-1, 10-phenathroline(NO2-phen)(3). The complexes were characterized by elemental analyses, in fared and electronic spectra, magnetic susceptibilities and ESR spectra, indicating antiferromagnetic spin exchange interactions between metal ions.展开更多
基金Supported by the National Natural Science Foundation of China.
文摘Three heterobinuclear complexes were synthesized, namely [Cu (oxpn) Co (L)2] (ClO4)2·xH2O(L= 2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen) , and 5-nitro-1, 10-phenanthroline (NO2-phen)), where oxpn represents N, N'-bis(3-aminopropyl) oxam-ido. Based on 1R, elemental analysis, conductivity measurement and electronic spectra, these complexes were characterized by an extended oxamido-bridged structure with Cu(Ⅱ) in a planar environment and Co(Ⅱ) in a octahedral environment. The symmetry of the cation is very close to C2v.The complexes were also characterized with variable temperature (4~300K) magnetic susceptibility, and the data were fit for the susceptibility equation derived from spin Hamilton, H= -2JS1.S2-DSx12 by least square strategy. The exchange integral, J, was found to be -22.36 cm-1 (for bpy);-15.45 cm-1 (for phen); -19. 10cm-1(for NO2-phen), indicating that there is a weak antiferromagnetic spin-exchange interaction between the metal ions.
基金Supported by the National Natural Science Foundation of China
文摘The copper( Ⅱ ) complex, [Cu(oxpn)Cu(tmen)2](ClO4)2 was synthesized, where oxpn is N, N' -bis ( 3-aminopropyl) oxamido and tmen is N, N, N' N' -tetram-ethylethylenediamine. The crystal is triclinic, space group P 1, a=1-2349(2), b = 1.3093(2), c=1. 3855(2) nm, α=61-88(1), β=69.49(1), γ=57.91(1)°? V = 1. 6589 nm3, Z = 2. Both copper( Ⅱ ) ions are in a square pyramidal coordination environment , and linked by oxamido bridge. The distance between them is 0. 526 nm. Variable temperature (4. 2-300 K) magnetic susceptibility data for this complex show that there exists a relatively large antiferromagnetic exchange interaction between the two copper( Ⅱ ) ions with a J value of-740. 40 cm-1.
基金Project supported by the National Natural Science Foundation of China.
文摘Six novel μ-oxamido heterobinuclear complexes, namely Cu(oxae)Ln(Me2bpy)2-(ClO4)3 (Ln=La, Nd, Gd, Tb, Ho, Er), where oxae denotes N, N'-bis(2-aminoethyl)oxamido dian-ion, Me2bpy is 4,4'-dimethyl-2,2'-bipyridyl, have been synthesized and characterized by elemental analyses, IR, conductivity measurements and electronic spectra. The temperature dependence of the magnetic susceptibility of Cu(oxae)Gd(Me2bpy)2(ClO4)3 has been meaured over the range 4-300 K. The least-squares fit of the experimental susceptibilities yielded J - 1.87 cm-1.The observed Gd(Ⅲ)-Cu(Ⅱ) coupling is ferromagnetic. One plausible mechanism that can cause a ferromagnetic coupling between Gd(Ⅲ) and Cu(Ⅱ) is discussed in terms of spin-polarization.
基金Supported by the National Natural Science Foundation of China
文摘Three dinuclear complexes were synthesized and designated as Cu(obp)CuL where obp =oxamidobis(propionato), L=2,2' -bipyridyl(bpy) (1), 1 , 10-phenathroline(phen)(2) and 5-nitro-1, 10-phenathroline(NO2-phen)(3). The complexes were characterized by elemental analyses, in fared and electronic spectra, magnetic susceptibilities and ESR spectra, indicating antiferromagnetic spin exchange interactions between metal ions.
