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Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.47A [2008] >
IJC-A Vol.47A(02) [February 2008] >
| Title: | Electronic parameters of aliphatic hydrazides with AM1 and PM3 Hamiltonians |
| Authors: | Suryanarayana, I
Ramam, V Ananta
Prasad, K M M Krishna
Rao, R Sambasiva |
| Issue Date: | Feb-2008 |
| Publisher: | CSIR |
| Abstract: | The optimized geometries and quantum chemically derived electronic parameters of physicochemical significance of mono- and di-aliphatic hydrazides are investigated using AMPAC 6.7 package. The number of hydrazide fragments enhances the stability as indicated by total energy and heat of formation. The partition of quantum chemical energy into its constituents is reported. The order of stability observed for different aliphatic acid hydrazides is: AdipHy > MalHy > OxalHy > AcetHy > FormHy. LUMO is on the second hydrazide fragment and HOMO as well as LUMO spread only on one of the fragments for dihydrazides with the exception for AdipHy. The shapes inferred from total electron density surface appear to be like banana for MalHy and nut (bent) for AdipHy. The negative charge on nitrogen of amino group is greater than that on oxygen of carbonyl and N of imino of hydrazide fragment. Linear (⍺) and third order (ϒ) polarizabilities increase from monohydrazides to dihydrazides, but the total dipole moments show the trend as: MalHy > AcetHy > AdipHy > FormHy > OxalHy. The data relating to parameters of biological/physical relevance and chemical reactivity are reported. These results from SEMO procedures with MNDO, AM1, PM3 and SAM1 Hamiltonians in gaseous phase reveal that the hydrazides participate in charge and orbital-based interactions. The bond lengths, bond angles and dihedral angles are same for optimized geometry in a typical study by changing SCF convergence limits and different quasi Newton algorithms. |
| Page(s): | 199-206 |
| ISSN: | 0376-4710 |
| Source: | IJC-A Vol.47A(02) [February 2008]
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