wizyta

od 2020-09-20

Title: Molecular motions in solid estradiol studied by nuclear magnetic resonance spectroscopy

Source: Solid State Nuclear Magnetic Resonance

Year : 1995

Abstract:

The temperature dependence of the proton nuclear magnetic resonance (NMR) relaxation time T-1 and second moment M(2) of polycrystalline beta-estradiol hemihydrate (1,3,5-estratriene-3,17 beta-diol) is measured at frequencies of 14 and 25 MHz. Below 260 K relaxation is found to be dominated by C-3 reorientation of the single methyl group in each molecule, characterized by an activation energy of 9.4 ±0.1 kJ/mol. Above 260 K another relaxation mechanism becomes evident, characterized by an activation energy of 22.0 ±2.0 kJ/mol and ascribed to motion of the water molecules in the solid.

DOI: 10.1016/0926-2040(95)00003-9   (Pobrane:  aktualizowanie)