Defect Crystal Structure of $$\alpha {\text{-N}}{{{\text{a}}}_{{0.5-x}}}{{R}_{{0.5 + x}}}{{{\text{F}}}_{{2 + 2x}}}$$ (R = Dy–Lu, Y) According to X-ray and Electron Diffraction Data. II: Defect Structure of the α-Na0.4R0.6F2.2 (R = Ho–Lu, Y) Nanostructured Crystals