Guest-dependent negative thermal expansion in a lanthanide-based metal–organic framework

Abstract

A lanthanide-based metal–organic framework (MOF) named SION-2, displays strong and tuneable uniaxial negative thermal expansion (NTE).

Theoretical prediction of negative thermal expansion in cubic VF3

“…Negative thermal expansion (NTE) materials have attracted extensive attention for application in optical, electrical, and engineering devices with precise thermal expansion. [1][2][3][4][5] A few NTE compounds, including oxides, [6][7][8] fluoride, [9][10][11] alloys, [12][13][14] cyanides, [15][16][17] Prussian blue analogues, [18][19][20] metal-organic frameworks, 21,22 and manganese nitrogen compounds, 23,24 have been discovered. Recently, some cubic metal fluorides were reported to exhibit interesting NTE phenomena.…”

Lowering the Energetic Landscape for Negative Thermal Expansion in 3D-Linker Metal–Organic Frameworks

“…This can be achieved through varying the building components such as the metal used, linker type and denticity, , guest species, , and framework topology . Introducing guests, such as CO 2 , H 2 O, He, and Na + , into the framework have shown to diminish NTE behavior, which is more pronounced at higher guest loadings where a greater portion of the pore volume is occupied and linker vibrational motions responsible for NTE are hindered. ,,− Linker variation is also particularly important, as it allows a direct investigation of the linker influence on NTE when the framework topology and metal clusters are constant. This was recently demonstrated in multivariate [Zn 2 (CO 2 ) 4 DABCO]-based MOFs, where substituting benzene-1,4-dicarboxylate (bdc) with increasing amounts of 2,3,5,6-tetramethyl-bdc ((CH 3 ) 4 -bdc) led to a decreased NTE magnitude, attributed to the steric bulk of (CH 3 ) 4 -bdc …”

C–H···S Hydrogen Bonds Governed Colossal Thermal Expansion: Two Concomitant Crystalline Forms of Ethionamide and 2-Thiobarbituric Acid

“…Several reports of such TE studies are reported in the literature, primarily corresponding to inorganic compounds, especially metal-based structures such as metal oxides, zeolites, MOFs, etc., ,− perhaps due to the ability of such materials response to the temperature gradient because of the prevalence of strong ionic or coordination bonds.…”