Chemical Reactivity

**Chapter 2**

**Abstract**

[Na(THPEN)]2

THPEN (N,N,N<sup>0</sup>

with a well agreement.

**1. Introduction**

and tight ion pairs.

**13**

(**6**) (where THEEN (N,N,N<sup>0</sup>

,N<sup>0</sup>

Complexes

Quantum Computational

Chemistry: Modeling and

*Rakesh Kumar and Sangeeta Obrai*

[Ca(THEEN)(PIC)]<sup>+</sup> (**1**), [Ca(THPEN)(H2O)2]

2+ (**4**), [Sr(THPEN)(H2O)2]2

,N<sup>0</sup>

Calculation of S-Block Metal Ion

The computational study of some s-block metal nitrophenolate complexes,

ligands and PIC� is 2,4,6-trinitrophenolate anion), is presented here using density functional theory (DFT) in its hybrid form B3LYP. The geometries of the title complexes are described by the quantum-chemical approach using input coordinates obtained from the previously synthesized and X-ray characterized diffraction data of [Ca(THEEN)(PIC)](PIC), [Ca(THPEN)(H2O)2](PIC)2, Ba(THPEN)(PIC)2,

(H2O)2]2(DNP)4 (where DNP is 3,5-dinitrophenolate). Only the primary coordination sphere of complexes (**1–6**) is optimized in the gaseous phase. Calculations of the energy gaps of frontier orbitals (HOMO-LUMO), 13C-NMR shifts and vibrational bands are carried out using B3LYP/6-31 g + (d,p)/LANL2DZ level of theory. The calculated geometric and spectral parameters reproduced the experimental data

**Keywords:** DFT, s-block metal complexes, nitrophenolates, tetrapodal ligands

The alkali and alkaline earth metal cations have inert gas electronic structures and are not expected to show any stereochemical requirements in their complex formation as do transition metal cations. They may be considered spherical even in the complex state. Their complexation is thus treated as recognition of spherical cations by organic ligands [1]. Depending upon the nature of the organic ligand and the anion, the metal ions can be separated as solvated ions, solvent separate, loose

Alkali and alkaline earth metal ions form a large number of solid complexes with podands [2–6]. The podands are inherently flexible because the two ends of the molecule are not tied simultaneously. Polypodal ligands are acyclic multidentate ligands containing more than three arms. They form an unlimited family of

[Na(THPEN)]2(PIC)2, [Sr(THPEN)(H2O)2]2(DNP)4 and [Ba(THPEN)

2+ (**2**), Ba(THPEN)(PIC)2 (**3**)

2+

2+ (**5**) and [Ba(THPEN)(H2O)2]2


