A new diphenylamine-functionalized ancillary-ligand-coordinated europium(III) β-diketonate complex showed incomplete photoexcitation energy transfer from a ligand to a EuIII ion. A solvatochromism study led to a balancing of the primary colors to obtain single-molecule white-light emission. Thermal-sensing analysis of the europium complex was executed. The europium complex, conjugated with a near-UV-light-emitting diode (395 nm), showed appropriate white-light-emission CIE color coordinates (x = 0.34 and y = 0.33) with a 5152 K correlated color temperature. © 2017 American Chemical Society.