The Data Management Plan (DMP) is prepared in the framework of the Latvian Council of Science Fundamental and Applied Research project No. lzp-2024/1-0162 "Influence of stoichiometry on radiation-induced effects in advanced two-phase functional materials for future thermonuclear fusion reactors" (project manager: Dr. chem. Artūrs Zariņš, 01.01.2025. - 31.12.2027., 300 000.00 EUR). Summary of the project: Advanced ceramic breeder pebbles consisting of lithium orthosilicate as the primary phase and lithium metatitanate as the secondary phase are developed as the European Union’s reference material for tritium breeding in future thermonuclear fusion reactors. The aim of this applied research project is to characterise the influence of stoichiometry on radiation-induced effects in single- and two-phase lithium orthosilicate-lithium metatitanate samples exposed to X-rays. The samples without and with deficiency and excess of lithium, silicon, and titanium will be prepared using the solid-state synthesis and analysed using different physico-chemical methods. Rietveld analysis of high-resolution powder X-ray diffraction (PXRD) patterns will be employed to determine the potential changes of crystalline phase lattice parameters and atomic positions. The formed and accumulated paramagnetic radiation-induced defect centres will be studied using electron paramagnetic resonance (EPR) spectroscopy. This project will contribute to the Smart Specialisation Strategy (RIS3) area “Smart energetics” and to the development of international nuclear energy sector.