Synthesis of nickel(II)-di(2,3-dichlorophenyl)carbazonate and its adduct formation with heterocyclic nitrogen bases

The nickel(II)-di(2,3-dichlorophenyl)carbazonate [Ni(D2,3DClPC)₂] complex has been prepared and characterized by elemental and spectral studies. The Ni^II chelate forms adducts with heterocyclic nitrogen bases, which were studied spectrophotometrically in monophase CHCl₃ media. Saturated monodentate bases such as pyrrolidine, piperidine, etc., form pentacoordinate adducts of 1:1 stoichiometry, whereas bidentate and unsaturated monodentate bases form hexacoordinated adducts with 1:1 and 1:2 metal–ligand stoichiometries respectively. The results are discussed interms of steric properties, basicity and ring structures of the heterocyclic bases.     

Dispersion relations for stark energy shifts in hydrogen atom

On the basis of an approximate but nonperturbative expression for the energy shift δE in the ground state of the hydrogen atom in the presence of an electric field of strength , we deduce that δE has a branch point at = 0, and an asymptotic behavior ln as → ∞. These properties lead to a twice-subtracted dispersion relation for δE as a function of . The dispersion relations in conjunction with the WKB approximation and the perturbation series allow us to (i) deduce the large-n behavior of the coefficient of ⁿ in the perturbation series for δE( ) including 1/n corrections and (ii) obtain the energy shift and the level width of the ground state for a large range of values of . The agreement with the earlier numerical calculations is very satisfactory.     

A study of adduct formation of heterocyclic nitrogen bases with nickel(II) chelate of di(6-chloro-2-methylphenyl)carbazone

The study of the adduct formation of Ni(II) di(6-chloro,2-methylphenyl)carbazonate has been undertaken by synthesising and characterizing it by magnetic susceptibility, UV-VIS, IR and 1H-NMR spectral measurements. The distorted square planar Ni(II) chelate forms adducts with heterocyclic nitrogen bases; spectrophotometric method has been employed for the study of the adduct formation in a monophase chloroform. Both bidentate and unsaturated monodentate heteronuclear nitrogen bases form hexacoordinated adducts with 1:1 and 1:2 stoichiometry, respectively (metalchelate:base). However, the saturated nitrogen bases form pentacoordinated adducts with 1:1 stoichiometry. The results are discussed in terms of basicity and steric factors of the bases.     

Dispersion relations for the Zeeman effect in the hydrogen atom

An analysis of the analyticity properties of the quadratic Zeeman energy shifts in the hydrogen atom leads us to once-subtracted dispersion relations for the energy levels. These relations (i) provide a compact representation of the general properties of the energy shifts, (ii) allow us to calculate energy levels for a wide range of values of the field.