Mn2+‐activated phosphors usually show green to red luminescence depending on the crystal field strength in the lattice. However, the severe intensity loss of Mn2+ luminescence at elevated temperatures remains to be a serious problem. Here, the observation of zero‐thermal quenching of Mn2+ red luminescence (λem = 620 nm) up to 500 K in Eu2+, Mn2+‐codoped BaMgP2O7 is reported. This phenomenon arises from an efficient energy transfer from sensitizers Eu2+ which, when singly doped, exhibits a substantial thermal‐induced enhancement of 5d→4f emission intensity at 400 nm, along with a high luminescence efficiency and a large UV light absorption capacity. The present results open up a new path to the exploration of Eu2+, Mn2+‐codoped materials for thermally stable red phosphors.

New three-dimensional, microporous metal-organic frameworks exhibiting reversible water adsorption, constructed from hexagonal [Co 3 (imda) 2 ] layers and N,NЈ-pillars, in which the dimensions of the channels are rationally adjusta-

A series of structurally related rigid imidazole ligands, 1,4-bis(imidazol-1-yl)benzene (L 1 ), 1,4-bis(benzoimidazol-1-yl)benzene (L 2 ), and 4,4′-bis(benzoimidazol-1-yl)biphenyl (L 3 ), have been utilized to construct coordination polymers. The reactions of CdX2 (X = BF4 − or ClO4 −) with these ligands afford three new three-dimensional networks, {[Cd(L 1 )3](BF4)2(CHCl3)2}∞ (1), {[Cd(L 2 )3](ClO4)2(CHCl3)4(CH3OH)2}∞ (2), and {[Cd(L 3 )3](ClO4)2}∞ (3). Compounds 1−3 are all α-Po metal−organic frameworks (MOFs) based on six-connected CdII nodes which are octahedrally coordinated by six nitrogen atoms of ligand molecules. Complex 2 represents a distorted α-Po framework with noninterpenetration, whereas 1 and 3 both exhibit a double interpenetrating α-Po network. These results suggest that the degree of interpenetration is tunable by ligand modifications, that is, varying the ligand spacer or terminal group. The three complexes exhibit a different void volume in their network. Gas adsorption measurements indicate that 3 possesses moderate gas-adsorption ability for CO2, and the progress of adsorption and desorption is reversible.

The hydrothermal reaction of CoCl 2 ‚6H 2 O with cis, cis,cis,cis,cis-1,2,3,4,5,6-cyclohexane-hexacarboxylic acid (L) generates a unique three-dimensional metal-organic framework (MOF) of [Co 3 (L-6H)(H 2 O) 6 ] n (1). X-ray crystallography reveals that each L-6H ligand changes its conformation to a trans,trans,trans,trans,trans form to connect nine Co(II) atoms, and each Co(II) atom is connected to three L-6H ligands, leading to a MOF structure with high symmetry of R3 h. The coexistence of planar and chair-shaped cyclic water hexamers is found in this MOF. Magnetic studies show the occurrence of the field-dependent magnetic transition.

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