Isostructural Family of Rare‐Earth MOFs Synthesized from 1,1,2,2‐Tetrakis(4‐phosphonophenyl)ethylene
The tetraphosphonic acid 1,1,2,2-tetrakis(4-phosphonophenyl)ethylene (H8L) was used as linker in the synthesis of eight new isostructural, phosphonate-based metal-organic frameworks of composition [M2(H2O)2(H2L)] ⋅ xH2O (M=Y3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+; 1.5<x<4), denoted as M-CAU-34. The compounds were synthesized under hydrothermal reaction conditions, using the corresponding metal nitrates as starting materials. The determination of the crystal structure was achieved by a combination of electron and powder X-ray diffraction (PXRD) data. In addition, a thorough characterization by thermogravimetric and elemental analysis, IR- and Raman-spectroscopy as well as H2O-sorption is given.