Silicophosphate can be used as bioactive materials for the growing of hydroxyapatite, or for protonic conduction. They are also interesting models for the study of diatoms, organisms containing a biological part with phoshorous and a shell of silica. The aim of this work is to develop methods to study by NMR interactions between 31 P and 29 Si nuclei. Due to the mobility, it is difficult to see interactions at ambiant temperature. In order to improve the signal to noise ratio and to study dynamic properties, we have used low temperature NMR. However, such study needs a special equipement and a rigorous calibration, which has been done using 207 Pb NMR on Pb(NO 3 ) 2 1 . This nucleus is particulary sensitive to the temperature.