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We report a KCaPOF:Eu phosphor with a new crystal structure. This phosphor has a large Stokes shift and converts near-ultraviolet light to red luminescence without absorption of other visible light. The mechanism was elucidated by applying a constrained density functional theory to the solved crystal structure.

The CO 2 absorption property of Li 4 SiO 4 was investigated by thermogravimetry. Two kinds of sintered Li 4 SiO 4 samples were prepared at 700? C and 1000? C. The CO 2 absorption rate of the powdered Li 4 SiO 4 samples was measured in 100 vol! CO 2 atmosphere at nine selected temperatures in the 620Ĭ700? C region, and the measured data were discussed by the rate theory. The CO 2 absorption reaction of the Li 4 SiO 4 would be a pseudo first order reaction. For these samples, apparent reaction rate constants k were measured at different measurement temperatures, and activation energies were estimated by the Arrhenius plot. For both the samples, the estimated activation energies were about 115 kJmol in the 620-660? C region and about 56 kJmol in the 680-700? C region. The large difference between these activation energies seems to depend on the surface state of the Li 4 SiO 4 particle reacting with CO 2 .

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