TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation: No general method for preparing nanoparticle (N1) and (N2) is given. Preferred Nanoparticle: The nanoparticle (N1) comprises a nitride crystal, at least one dimension of the crystal being of a nanoscale dimension; and at least one capping agent provided on a surface of the nitride crystal and containing an electron-accepting group for passivating nitrogen atoms at the surface of the crystal. Preferred Components: The capping agent further contains an electron-donating group for passivating metal, boron or silicon atoms at the surface of the crystal. The capping agent includes a capping agent having an electron-accepting group for passivating nitrogen atoms at the surface of the crystal and an electron-donating group for passivating metal, boron or silicon atoms at the surface of the crystal. The electron accepting group includes a metal (preferably Group II metal or a Group III element, especially scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), zirconium (Zr), silver (Ag), molybdenum (Mo), ruthenium (Ru), palladium (Pd), cadmium (Cd), tantalum (Ta), tungsten (W), osmium (Os), iridium (Ir), platinum (Pt), gold (Au) and mercury (Hg)), boron or silicon. The electron accepting group comprises a metal amine, metal carboxylate, metal acetoacetonate, metal sulfonate, metal phosphonate, metal thiocarbamate, or metal thiolate. The electron-donating group is selected from phosphines, phosphine oxides, carboxylic acids, carboxylates, amines, sulfonates, esters, thiols and thiolates. The nitride crystal is a crystal of a metal, boron or silicon nitride having the formula Mx'Ny'. The nitride crystal comprises at least two metals, boron or silicon and has formula M1x1M2x2M3x3...MnxnNy. The metal is a Group III metal. The nitride crystal is a crystal of indium nitride. The capping agent includes a zinc carboxylate.M=metal, boron or silicon;x' and y'=integers;M1, M2, M3...Mn=metals, boron or silicon;x1, x2, x3...xn=quantities of the metals, boron or silicon;andy=quantity of nitrogen. EXAMPLE - Indium iodide (300 mg), sodium amide (500 mg), hexadecane thiol (308 mu l), zinc stearate (379 mg) and diphenyl ether (20 ml) were heated rapidly to 250 degrees C. Over the course of 40 minutes 0.25 ml portions of the reaction mixture were removed and diluted with cyclohexane (3 ml) and any insoluble material was removed using a centrifuge to obtain clear solutions of emissive indium nitride nanocrystals.