Structure and Stability of the Low-Temperature Modification of Compounds Cs3LnCl6 (Ln = La-Gd)

Crystal growth and scintillation properties of Cs3CeCl6 and CsCe2Cl7

“…Cs 3 CeCl 6 and CsCe 2 Cl 7 are congruently melting compounds that exist in the CsCl-CeCl 3 system [10], which makes them suitable for practical crystal growth from the melt by Bridgman technique. Cs 3 CeCl 6 has a density of 3.4 g/cm 3 [11] and melts congruently at 804 1C and undergoes solid-solid state phase transition at 401 1C [12]. Its hightemperature phase crystallizes in cubic elpasolite type and a lowtemperature phase in monoclinic crystal structure [13].…”

Thermodynamic assessment of LiCl–NdCl3 and LiCl–PrCl3 quasi-binary systems

“…According to the unpublished work of Sun and Qiao [31] on molten salt phase diagram evaluation by pattern recognition, the existence of the compound LiNd 2 Cl 7 in the LiCl-NdCl 3 system was strongly supported. It is intriguing that the compound LiNd 2 Cl 7 reported by Kim and Okamoto [19] and Sun and Qiao [31] was not confirmed by XRD or even not detected by other experimental researchers [17,18,[20][21][22][23][24][25][26][27][28][29][30]. Two probable reasons may be provided: one is that the compound only exists in a very limited temperature range, the phase transition should have occurred during the quenching of the XRD sample.…”

“…In the systematic phase diagram investigations of MCl-LnCl 3 binary systems by Differential Thermal Analysis (DTA) combined with high temperature X-ray analysis and e.m.f. measurements [20][21][22][23][24][25][26][27][28][29][30], Seifert and co-workers set up a series of phase diagrams for the MX-LnX 3 (M = Alkali metal, Ln = Rare earth metal, X = halide) binary systems and detected the CsLn 2 Cl 7 in all the chloride systems from cerium chloride (CeCl 3 ), the RbLn 2 Cl 7 starting from samarium chloride (SmCl 3 ) and KLn 2 Cl 7 from europium chloride (EuCl 3 ). According to this systematic trend, i.e., the smaller atomic number of alkali and lanthanide, the more difficult for MLn 2 Cl 7 to form in the corresponding system, LiLn 2 Cl 7 should not exist before europium chloride (EuCl 3 ).…”

Unusual nature of lanthanide chloride–alkali metal chloride M3LnCl6 compounds in the solid state

“…So, each M cation is surrounded by 6 and each M-by 12 chloride ions. According to Seifert [19], due to enormously large temperature factors for all atoms except Ln, such a description can be considered only formally.…”

“…Cubic, elpasolite-type crystal structure is realised in the high temperature modifications of the M 3 LnCl 6 compounds [19]. The correct formula of these compounds should be written as M 2 M LnCl 6 .…”