A novel multi-metal co-doped phosphor La0.9Ce0.05Li0.05Mn0.05PO4 was obtained by calcining its precursor La0.9Ce0.05Li0.05Mn0.05PO4 center dot 0.92H(2)O at 750 degrees C in the air. The hydrate precursor was synthesized via solidstate reaction at 60 degrees C. The reason why the spin-forbidden (T-4(1)((4)G) -> (6)A(1)(S-6)) transition of Mn2+ is released in this product is because of the introduction of Li+ ions. The most probable mechanism was estimated with three methods. The results show that the Iso-temperature method is a local optimal one while both Masterplots and Nonlinear model-fitting methods are global optimization methods. The value of pre-exponential factor A was obtained the reaction mechanism. (C) 2015 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.