Li2Ca5Tb(BO3)5: An orthoborate with large spherical hollow cages

KLi2RE(BO3)2 (RE = Dy, Ho, Er, Tm, Yb, and Y): Structural, Spectroscopic, And Thermogravimetric Studies on a Series of Mixed-Alkali Rare-Earth Orthoborates

“…The bands between 600 and 1600 cm –1 resulting from the vibration of planar BO 3 3– groups can be classified into the following four types: , (I) in-plane bending (ν 4 ; 600–700 cm –1 ), (II) out-of-plane bending (ν 2 ; 750–770 cm –1 ), (III) B–O symmetric stretching (ν 1 ; ∼905 cm –1 ), and (IV) B–O asymmetric stretching (ν 3 ; 1000 and 1600 cm –1 ). Clearly, the intense band at about 928 cm –1 can be assigned to the ν 1 mode of BO 3 group, which is also a common feature to other rare-earth orthoborates such as Li 2 Ca 5 Tb­(BO 3 ) 5 and KCaLa­(BO 3 ) 2 . Alike the Raman spectra, the IR bands of KLi 2 RE­(BO 3 ) 2 (Figure a) also show global shifts due to the varying sizes of the RE cations.…”

Synthesis and crystal structures of novel alkali rare-earth orthoborates K3RE3(BO3)4 (RE = Pr, Nd, Sm–Lu)

“…6. Generally, all absorption bands in the IR spectra from 400 to 1700 cm -1 can be assigned to the trigonal planar BO 3 groups [51][52][53]. The pronounced broad absorption bands between 1000 and 1600 cm -1 originate from the B-O asymmetric stretching (m3) of the BO 3 groups.…”

“…6b). Below the 400 cm -1 region is dominantly contributed by the stretching modes of RE-O bonds and K-O bonds; the complex lattice vibrations at this region can be explicitly distinguished [51][52][53] from the rest of the spectral intensity. The most intensive peaks in the spectra located around between 900 and 980 cm -1 fit well to the stretching vibrations (m1 modes) of BO 3 groups which are formally Raman active.…”

Two new rare-earth borates Sr2Tb3B27−δO46 and Ba2Eu3B27−δO46 (δ = 2/3): syntheses, crystal structures, and luminescence properties

“…78 The lifetime values reported in this work are also comparable with those in other phosphors activated by Tb 3+ and Eu 3+ , such as M 3 Eu 2 (BO 3 ) 4 (M = Ba, Sr), Li 2 Ca 5 Tb(BO 3 ) 5 , and TbCa 4 O(BO 3 ) 3 . [79][80][81]…”