Further work on the calculation of d-orbital energies of cobalt porphyrins from electron spin resonance data

1980 ◽  
Vol 19 (4) ◽  
pp. 1072-1073 ◽  
Author(s):  
W. C. Lin
2011 ◽  
Vol 62 (2) ◽  
pp. 181-186 ◽  
Author(s):  
Pavle Premović ◽  
Budimir Ilić ◽  
Dragan Đorđević

A new method for determining the concentration of vanadyl ions in claysA novel and simple method for quantitatively determining the concentration of vanadyl ions in clays using electron spin resonance data has been developed. Several vanadyl standards with concentrations between 200-1000 ppm were prepared in a mixture of glycerol and kaolinite (KGa-2). The anisotropic electron spin resonance (ESR) spectra were recorded at room temperature, and the specific intensity of the line (attributed to nuclear spin m = -5/2||) was determined. For vanadyl concentrations between 50 ppm and 200 ppm, the standards must be prepared by mixing kaolinite with known vanadyl content (FBT2A-03) and kaolinite (GB1) containing no vanadyl. The method is applicable without modification to other clays and clay-rich sediments containing vanadyl ions. The whole procedure is very suitable for routine work.


1978 ◽  
Vol 56 (10) ◽  
pp. 1311-1318 ◽  
Author(s):  
Laurence K. Thompson ◽  
Baratham S. Ramaswamy ◽  
Robert D. Dawe

A series of nickel(II) and copper(II) complexes of the title ligand are reported which appear to exhibit predominantly pseudo-octahedral structures in the solid state. Anion bridged dimeric structures are proposed for both nickel and copper; [Ni2(NTB)2X2]Y2 (X = Y= Cl, Br; X = Cl, Br, NCS; Y = BPh4), [Cu2(NTB)2X2]X2•2H2O (X = Cl, Br). The other octahedral derivatives appear to be monomeric; (Ni(NTB)X2] (X = NO3, NCS), [Ni(NTB)-(H2O)X]Y (X = NCS, Y = BPh4; X = CH3CN, Y = (ClO4)2), [Ni(NTB)(H2O)2]X2•2H2O (X = ClO4, BF4), [Cu(NTB)(NO3)2]•H2O. Five-coordinate derivatives were uncommon and in the case of three copper complexes trigonalbipyramidal structures are suggested in the solid state; [Cu(NTB)CI]BPh4, [Cu(NTB)(H2O)]X2•nH2O (X = BF4, n = 0; X = ClO4, n = 1). In acetone solution ail the copper complexes appear to be five-coordinate. Electron spin resonance data confirm trigonalbipyramidal solution structures and indicate [Formula: see text]with very small values of [Formula: see text] (60 − 80 × 10−4 cm−1).


Author(s):  
Brian Burton ◽  
Thomas A. Claxton ◽  
Stephen J. Hamshere ◽  
Howard E. Marshall ◽  
Richard E. Overill ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document