Pulse methods of electron paramagnetic resonance (EPR) are used to measure relaxation behavior and crystal environment of ¹⁷¹Yb impurity ions in a single crystal of yttrium orthosilicate (Y₂SiO₅) grown with an isotopically pure ²⁸Si with a zero value of the nuclear spin. It is shown that for an ytterbium ion substituting an yttrium ion in a six-fold oxygen environment, the spin-lattice relaxation time is approximately an order of magnitude greater than that for the ytterbium ion substituting an yttrium ion in a seven-fold oxygen environment. Measurements of the phase relaxation times by two-pulse Hahn echo and Carr-Purcell-Meiboom-Gill (CPMG) multiple pulse sequence revealed strong influence of spectral diffusion on the time of phase relaxation at temperatures less than 9 K. Two magnetically different ytterbium paramagnetic centers were definitely attributed to two structurally different ytterbium positions in the Y₂SiO₅ crystal lattice relative by the electron spin echo envelope modulation (ESEEM) method. Based on the data obtained, the most probable location of the ¹⁷¹Yb³⁺ ion in the Y₂SiO₅ crystal lattice was determined.

This is a brief overview of the development stages of two branches of magnetic resonance - electron paramagnetic and nuclear magnetic resonances (EPR and NMR), started with the first attempts to observe the resonant absorption of electromagnetic waves in paramagnets. It is described in more detail how this line of research was formed at Kazan University, in the USSR. All the most significant publications about the creation of an experimental EPR and NMR base at the University from the time when the first spectrometers were manufactured to today's developments are noted. A brief summary of the development of magnetic resonance research methods and their applications in a wide variety of fields of knowledge until 2010, when significant changes began in the system of the Higher School (Universities) of Russia and the Academy of Sciences, which left a deep imprint on the development of science in Russia as a whole, and on the development of one of its most important areas, "Magnetic resonance in materials science and in biomedical research", in particular is given. The main achievements of the University teams using these methods in their research in physics, chemistry, biology and medicine, oil and gas technologies, as well as for solving problems in various sectors of economy over the past decade, are presented. Current trends in the development of magnetic resonance methods in the world, the place of Russia, and the relative contribution of its leading teams are noted. Annexes 1 and 2 contain a list of Doctor of Science and Ph.D. theses made at Kazan University in this area, including dissertations, the performance or certification of which are related to Kazan University. Annex 3 contains the list of events organized in Kazan and related to the Kazan school of radiospectroscopy.