Microwave spectrum and nitrogen-14 nuclear electric quadrupole coupling constants in cis-thionylimide and iminosulfur oxydifluoride: orientation and analysis of the electric field gradients

Abstract

The I4N nuclear quadrupole coupling constants for DNSOFz have been measured. They are xno = 2.44 f 0.25 MHz, X b b = -0.67 & 0.85 MHz, and xcc = -1.77 & 0.67 MHz. These data, when combined with previous measurements for HNSOF2, HNSO, and Dh'SO, give the orientation and magnitudes of the principal axes of the electric field gradients in both compounds. h-otable differences in the magnitudes are observed. The orientation of electric field gradient tensor in the molecular symmetry planes are respectively for Hl-SOF, and H N S O about 17 and 26' from the N-S bond direction.The electronic structure of the two compounds has also been analyzed by ab initio MO-SCF calculations. The agreement with experiment for the relative signs, magnitudes, and orientation of the computed electric field gradient tensor is very satisfactory. The calculations also indicated that the major source of the differences in the quadrupole coupling constants can be attributed to increased electron density in the nitrogen p orbital perpendicular to the symmetry plane in HNSOF, and increased a-bonding character in the nitrogen-sulfur bond.

Preparación, estudios estructurales y espectroscópicos en compuestos N-sulfinilimínicos (R-NSO)

“…La tabla 2.5 muestra los valores del momento dipolar de la forma syn del H-N=S=O, calculados utili zando diferentes modelos teóricos. Se incluye el valor experimental determinado mediante el análisis del espectro de micro ondas [18,21], El momento dipolar es la derivada primera de la energía con respecto a un campo eléctrico aplicado. Es una medida de la asimetría de la distri bución de carga en la molécula, y está dado por un vector en tres dimensiones.…”