Cerocene and Lanthanocene Chalcogenides: Synthesis, Structure, and Luminescence

Abstract

A series of lanthanide chalcogenides {[η5–1,3-(Me3C)2C5H3]2Ln}2(μ-η2:η2-Te2) (Ln = Ce 1, La 2), {[η5–1,3-(Me3C)2C5H3]2Ln­(THF)}2(μ-Se) (Ln = Ce 3, La 4), and {[η5–1,3-(Me3C)2C5H3]2Ln­(THF)}2(μ-Te) (Ln = Ce 5, La 6) can be readily obtained by the reaction of the alkyl complexes [η5–1,3-(Me3C)2C5H3]2Ln­(CH2C6H4-o-NMe2) with elemental selenium or tellurium in the presence of 9-borabicyclo[3.3.1]­nonane (9-BBN). The reaction of the alkyl complexes [η5–1,3-(Me3C)2C5H3]2Ln­(CH2C6H4-o-NMe2) with 9-BBN in 1:2 molar ratio afforded the lanthanide (cyclooctane-1,5-diyl)­dihydroborate complexes [η5–1,3-(Me3C)2C5H3]2Ln­[(μ-H)2BC8H14] (Ln = Ce 7, La 8) concomitant with the (Me2N-o-C6H4CH2)­BC8H14 release, indicating that [η5–1,3-(Me3C)2C5H3]2LnH may be the reactive species for the synthesis of lanthanide chalcogenides. All the new compounds were characterized by various spectroscopic methods, and their solid-state structures were further confirmed by single-crystal X-ray diffraction analyses. Luminescence spectroscopy was also employed to characterize complexes 1–6. The Ce­(III) complexes 3 and 5 display distinct luminescence properties at room temperature, as compared to the corresponding La­(III) complexes 4 and 6. The complex {[η5–1,3-(Me3C)2C5H3]2Ce­(THF)}2(μ-Te) (5) exhibits unexpectedly red emission in solution which is found to depend strongly on the excitation wavelength.

Epitaxial Growth of MgGa2O4/CsPbBr3 Heterostructure with Controlled Defect Tolerance for Dynamic Photoluminescence

“…[ 7,8 ] Since dynamic PL properties are associated with trap filling in the electronic transition levels, rich and tunable defects are urgent for dynamic PL implementation. [ 7–11 ] Currently, only a few dynamic PL materials have been reported in several inorganic persistent phosphors. Therefore, it remains a challenge to explore novel strategies and new systems to construct diverse and color controllable dynamic PL in versatile systems.…”

“…Thus, the construction of non‐charge transfer type epitaxial layers are an ideal choice for ensuring stable luminescence of perovskite and holding promise to achieve dynamic PL. [ 33 ] Notably, the spinel MgGa 2 O 4 crystal exhibits blue luminescence originating from the self‐activation of octahedral GaO 6 , [ 11 ] in which the strong binding energy between photogenerated electron (Ga 3+ ) and hole (O 2− ), defined as Frenkel excitons, is expected to prevent the interface charge–transfer, making it a promising epitaxial layer to realize anti‐fluorescence quenching. To date, there is still no report of dynamic PL modulated by engineering defect tolerance in halide perovskite heterostructure.…”

Dinuclear ytterbium(iii) benzamidinate complexes with bridging S32−, Se22− and Te22− ligands: synthesis, structure and magnetic properties

“…15 a It is worth mentioning that the benzamidinate ligands used in this work possess SiMe 3 groups which have been proved to be useful in stabilizing Ln( ii ) complexes. 18 Although similar dinuclear linkages were reported in other lanthanide compounds, 1 a , e ,3,4,19 only a handful of them have been synthesized via divalent lanthanide complexes, 1 e ,3–4,19 g , n and ytterbium analogues are very scarce. 20 The magnetic properties of these compounds were studied as well which revealed that 3 represents a rare example of lanthanide telluride SMMs.…”