ИСТИНА

Previously we have exploited the increased sensitivity and resolution of high-frequency electron paramagnetic resonance (EPR) to study the tissues of calcified aorta walls and synthesized nano-HAp samples. Now we have spread our research onto the investigations of different nano-HAp samples by means of X- (10 GHz) and W- band (94 GHz) EPR and double resonance (ENDOR) pulsed techniques. It is demonstrated that during wet synthesis process nitrate anions from the by-products could incorporate into the nano-HAp. The comparison of the experimental data with the spectroscopic and structural information as followed from ab initio DFT calculations allowed us to determine the structure and location of NO3-/NO32- defect.