Semiconductor nanoparticles, method for producing semiconductor nanoparticles, and light emitter

A method for producing semiconductor nanoparticles, the method comprising:

• weighing a Ag compound, a Ge compound, and a S compound such that a content ratio of the Ag component to the Ge component in a compound semiconductor of the semiconductor nanoparticles to be produced is 1.0 or more and less than 7.5 in terms of molar ratio;
• dissolving the weighed compounds in a solvent so as to produce a Ag—Ge—S mixture solution;
• and
• heating the Ag—Ge—S mixture solution at a reaction temperature of 150° C. or higher and lower than 250° C. so as to synthesize the semiconductor nanoparticles having an average particle size of 9 nm or less.