Single crystals of new bromosilicate compound Ca3SiO4Br2 were grown out of high-temperature Ca2SiO4/CaBr2 melts by the slow cooling process. Colorless, transparent and flaky crystals of Ca3SiO4Br2 were directly isolated from the final solid coagulation. The as-obtained crystals were investigated by energy dispersive X-ray spectrometer (EDS), scanning electron microscope (SEM) and polarized light microscope (PLM). The structure of the new Ca3SiO4Br2 compound was determined by single-crystal X-ray diffraction, and it crystallized in the triclinic system, space group P-1 with unit cell parameters a=8.0051(18) angstrom, b=8.720(3) angstrom, c=11.749(3) angstrom, alpha=69.07(0)degrees, beta=89.98(0)degrees, gamma=75.46(0)degrees and V=737.88(196) angstrom(3), Z=3. Interestingly, a significant amount of Eu2+ enters the Ca3SiO4Br2 phase, and the Eu2+-doped Ca3SiO4Br2 phosphor shows a strong blue emission band centered at 469 nm under 365 nm UV light, which demonstrates that Ca3SiO4Br2:Eu2+ is a promising blue phosphor for use in white light LEDs. (C) 2010 Elsevier B.V. All rights reserved.