Zeolitic imidazolate frameworks (ZIFs) are a class of metal-organic frameworks (MOFs) that are topologically isomorphic with zeolites. [1] . ZIFs are composed of tetrahedrally-coordinated transition metal ions (e.g. Fe, Co, Zn) connected by imidazolate linkers.

Dec 1, 2019 · For these two purposes, we perform a systematic study by varying the solvothermal synthesis condition of ZIF-4 (Zn[C 3 N 2 H 3] 2) crystals. We found that pure ZIF-4 crystals could be obtained at synthetic temperatures (T s) below 383 K …

Mar 18, 2019 · Here, we show that simultaneous high-pressure and high-temperature conditions result in complex behaviour in ZIF-62 and ZIF-4, with distinct high- and low-density amorphous phases occurring...

Dec 20, 2022 · An initial correlation between the mechanical properties of ZIF-4 and mid-range structural parameters, such as free volume, is presented . The structure–properties relationship of ZIF-4 is plagued by several obstacles, such as small pressure needs and small structure characterization.

We use ab initio density functional theory (DFT) to elucidate the mechanical properties of two topologically distinct zeolitic imidazolate framework (ZIF) materials: ZIF-4 and ZIF-zni, both...

Oct 9, 2017 · We first studied the evolution in structure of ZIF-4, which is composed of Zn (Im) 4 tetrahedra linked by Zn–N coordinative bonds (Fig. 1a, b), and forms a three-dimensional, crystalline network...

Jan 24, 2024 · We investigate the microscopic mechanism of the thermally induced ambient pressure ordered–disordered phase transitions of two zeolitic imidazolate frameworks of formula Zn(C 3 H 3 N 2) 2: a porous (ZIF-4) and a dense, non-porous (ZIF-zni) polymorph via a combination of data science and computer simulation approaches.

Mar 19, 2010 · ZIF-4, a metal-organic framework (MOF) with a zeolitic structure, undergoes a crystal–amorphous transition on heating to 300 ° C. The amorphous form, which we term a-ZIF, is recoverable to ambient conditions or may be converted to a dense crystalline phase of the same composition by heating to 400 ° C.

Abstract: Twelve zeolitic imidazolate frameworks (ZIFs; termed ZIF-1 to -12) have been synthesized as crystals by copolymerization of either Zn (II) (ZIF-1 to -4, -6 to -8, and -10 to -11) or Co (II) (ZIF-9 and -12) with imidazolate-type links.

Nov 6, 2024 · The porous ZIF-4 phase transforms into ZIF-4-cp through pore closure, while the latter has a phase transition in higher pressure regimes to ZIF-4-cp-II, a transformation which involves subtle changes in the orientation of four member rings with respect to unit cell vectors.