Exceptionally low shear modulus in a prototypical imidazole-based metal-organic framework
Document Type
Article
Publication Date
2-29-2012
Abstract
Using Brillouin scattering, we measured the single-crystal elastic constants (C ij's) of a prototypical metal-organic framework (MOF): zeolitic imidazolate framework (ZIF)-8 [Zn(2-methylimidazolate) 2], which adopts a zeolitic sodalite topology and exhibits large porosity. Its C ij's under ambient conditions are (in GPa) C 11=9.522(7), C 12=6.865(14), and C 44=0.967(4). Tensorial analysis of the C ij's reveals the complete picture of the anisotropic elasticity in cubic ZIF-8. We show that ZIF-8 has a remarkably low shear modulus G min1GPa, which is the lowest yet reported for a single-crystalline extended solid. Using ab initio calculations, we demonstrate that ZIF-8's C ij's can be reliably predicted, and its elastic deformation mechanism is linked to the pliant ZnN 4 tetrahedra. Our results shed new light on the role of elastic constants in establishing the structural stability of MOF materials and thus their suitability for practical applications. © 2012 American Physical Society.
Publication Title
Physical Review Letters
Recommended Citation
Tan, J.,
Civalleri, B.,
Lin, C.,
Valenzano, L.,
Galvelis, R.,
Chen, P.,
Bennett, T.,
Mellot-Draznieks, C.,
Zicovich-Wilson, C.,
&
Cheetham, A.
(2012).
Exceptionally low shear modulus in a prototypical imidazole-based metal-organic framework.
Physical Review Letters,
108(9).
http://doi.org/10.1103/PhysRevLett.108.095502
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/10088