LOW-TEMPERATURE SINGLE-CRYSTAL X-RAY-DIFFRACTION, H-1 AND C-13 SOLID-STATE NMR AND N-14 NQR STUDIES OF 1,8-BIS(DIMEAHYLAMINO)NAPHTHALENE

Low-temperature C-13 and H-1 MAS NMR and N-14 NQR spectra of solid 1,8 -bis(dimethylamino)naphthalene (DMAN) have been measured. X-Ray diffra ction shows that the molecule is more symmetric than at room temperatu re. The low-temperature geometry of DMAN is very similar to the ab ini tio optimized geometry. Solid-state NMR and nuclear quadrupole resonan ce (NQR) confirm the symmetry of the molecule at low temperature despi te the asymmetry of intermolecular interactions in the crystal. Experi mental values of the principal components of electric field gradients at N-14, which characterize the properties of the lone pair electrons of the nitrogen atoms, are in good agreement with the ab initio calcul ated values.