Highly fluorescent silver nanoparticles (Ag-NPs), soluble in a ferroelectric host of polymer molecules such as poly(vinylidene fluoride(PVF2), have been created in the form of nanofluids. The content of Ag-NPs (flocculates)is varied in steps 0.1–0.2 wt% up to a value of 5.0 wt% in tailoring a broad green emission band over 520–620nm out of a hybrid percolation Ag–PVF2 composite. A maximum intensity arises in this band at as small a percolation threshold as 0.1wt% Ag-NPs. It contains three distinct bands of peak values 541, 565, and 582nm in an Ag-NPs tunable response of the localized surface plasmons. The emission-dependent anti-Stokes excitation spectrum contains a similar group of three bands 348, 401, and 421 nm. For Ag-contents above 0.1 wt%, interdependent intensities in the emission and excitation bands drop rapidly by as much as five times, conferring a metal–polymer percolation network. The results open wide applications for biological labels and light emitters using such nanofluids.

We present a survey of recent theoretical studies of radiation-induced point defects in simple oxides with emphasis on highly ionic MgO, partly-covalent corundum (Al2O3) and ferroelectric KNbO3. The atomic and electronic structure of the electronic (F+ and F centers) and hole centers, as well as interstitial atoms therein are discussed in light of the available experimental data. Results for defect diffusion and photo-stimulated F+ → F center conversion are also analyzed.
Nuclear Instruments and Methods in Physics Research Section B, Volume 141, 1998, Pages 1-15

We present a short survey of the optical properties of primary radiation-induced point defects in alkali halides, simple oxides and some ABO3 perovskites. We discuss in details the optical properties of single electron F and F+ centers in rock-salt (f.c.c.) alkali halides and oxides and show that the Mollwo–Ivey law well-known for the F-type centers in alkali halides may be extended for other rock-salt structure insulators. We also discuss the major differences in point defect production mechanisms in halides and oxides. We show that the Rabin–Klick diagram may be generalized for a whole family of alkali halides. The F-type center migration and aggregation into metal colloids in alkali halides and oxides is also discussed.
Nuclear Instruments and Methods in Physics Research Section B, Volume 268 (2010) pp. 3084-3089

Optical absorption measurements were used to monitor the thermal annihilation of oxygen vacancies (F-centers) in thermochemically reduced MgO crystals. The annihilation characteristics were sample-dependent and varied strongly with the F-center concentration. Different mechanisms for the destruction of F centers are suggested depending on their concentration.
Solid State Communications, Volume 118, 2001, pp.163-167