Crystal Structure and Thermal Expansion of Ca2Y2Si2O9

High-Temperature Neutron Diffraction Study of Y4Al2O9

“…Another possibility is by an order-disorder phase transformation at a higher temperature between 1665°C and the melting point ( about 2000°C (9, 24)). Recently, a disorder arrangement of Si O groups has been shown in the structure analysis of an isostructural compound Ca Y Si O (25).…”

Photoluminescence of Y4Al2O9:Re (Re=Tb3+, Eu3+) under VUV excitation

“…However, it is scarcely found the investigation on photoluminescence properties of rare earth ions doped Y 4 Al 2 O 9 in the VUV region. It has been reported that the space group for the crystal structure of Y 4 Al 2 O 9 is P2 1 /c of monoclinic system [10]. The Al atoms are coordinated to four oxygen atoms, the Y atoms are coordinated to either six or seven oxygen atoms [10,11], and its site symmetry is C 1 [12].…”

“…It has been reported that the space group for the crystal structure of Y 4 Al 2 O 9 is P2 1 /c of monoclinic system [10]. The Al atoms are coordinated to four oxygen atoms, the Y atoms are coordinated to either six or seven oxygen atoms [10,11], and its site symmetry is C 1 [12]. In the former investigation, it has been reported that emission spectra of Y 4 Al 2 O 9 :Eu 3+ were dominated by the electric dipole tran- * Corresponding author.…”

The luminescence of Pr3+ ions doped in Y4Al2O9 by sol–gel synthesis

“…However, only a few spectroscopic investigations on YAM host doped with rare earth ions have been reported [6][7][8][9]. It has been reported that the space group for the crystal structure of Y 4 Al 2 O 9 is P2 1 /c of monoclinic system [10,11]. The Al atoms are coordinated to four oxygen atoms, the Y atoms are coordinated to either six or seven oxygen atoms [11], and its site symmetry is C 1 [12].…”

“…It has been reported that the space group for the crystal structure of Y 4 Al 2 O 9 is P2 1 /c of monoclinic system [10,11]. The Al atoms are coordinated to four oxygen atoms, the Y atoms are coordinated to either six or seven oxygen atoms [11], and its site symmetry is C 1 [12]. There are four formula units in the unit cell of the room temperature phase of Y 4 Al 2 O 9 and four different rare earth sites in the asymmetric unit.…”