Abstract
M[BeSi2N4] (M=Sr,Eu), crystallizing in the hexagonal space group P (6) over bar 2c, was synthesized from Sr(NH2)(2), Be3N2, and "Si(NH)(2)" in W crucibles under a N-2 atmosphere in a radio-frequency furnace. The crystal structure was solved from powder X-ray diffraction data by the charge-flipping method (Sr[BeSi2N4]: a=4.86082(2), c=9.42264(4)angstrom, Z=2;Eu[BeSi2N4]: a=4.85848(1), c=9.41615(4)angstrom). M[BeSi2N4] contains a highly condensed rigid network of trigonal planar [BeN3] units that are connected to Si2N7 double tetrahedra by common vertices. M[BeSi2N4] (M=Sr,Eu) are the first examples of nitridoberyllosilicates and are isotypic to the oxoberyllate Sr[Be3O4]. Eu2+-doped Sr[BeSi2N4] and Eu[BeSi2N4] show orange-trapped exciton emission (lambda(em)=605nm, fwhm approximate to 126nm), whereas Ce3+-doped samples of Sr[BeSi2N4] show nontypical yellowish-orange luminescence. Sr[BeSi2N4] has a large band gap of approximate to 4.4eV and shows high chemical and thermal stability. Eu2+-doped beryllates with regular 4f(6)5d(1)4f(7)-emission could be interesting for future application in LEDs upon doping with Eu2+ or Ce3+ due to large band gaps, rigid networks, and chemical and thermal stability.
Item Type: | Journal article |
---|---|
Faculties: | Chemistry and Pharmacy > Department of Chemistry |
Subjects: | 500 Science > 540 Chemistry |
ISSN: | 0947-6539 |
Language: | English |
Item ID: | 67470 |
Date Deposited: | 19. Jul 2019, 12:22 |
Last Modified: | 04. Nov 2020, 13:49 |