Study of the paraelectric phase of tri-sarcosine calcium chloride by nuclear quadrupole resonance of35CI

Abstract

Abstract The temperature dependence of the 35Cl pure nuclear quadrupole resonance in tri-sarcosine calcium chloride (CH3 NHCH2COOH)3 CaCl2 was measured in the temperature interval 320 K-127 K (paraelectric phase). The measured chlorine nuclear quadrupole resonance frequency 2.175 MHz at room temperature is one of the lowest reported until now. Taking into account the known crystallographic data and the point charge model, the electric field gradient (EFG) tensor at the place of 35Cl nuclei was calculated. The obtained EFG tensor and the measured frequency of 35Cl nuclear quadrupole resonance in tri-sarcosine calcium chloride enabled us to determine the Sternheimer factor γ∞ for chlorine. The agreement of our results with the values of γ∞, obtained by other methods, is acceptable. The important role which play the hydrogen bonds in this compound in determining the EFG at the place of chlorine nuclei is discussed.