Fig. 1: Structural, crystallographic, and thermal properties of modified zeolitic imidazolate frameworks.
From: Continuous structure modification of metal-organic framework glasses via halide salts
a Sketch of polymerized zeolitic imidazole framework and its imidazolate-based linkers (left) and the added halide salts (right). b X-ray diffraction patterns of ZIF-4, ZIF-8, and ZIF-62, including simulated (CCDC deposition numbers: ZIF-4:602538, ZIF-8:1429243, and ZIF-62:671070) and experimental crystalline forms and experimentally formed glasses upon co-melting with benzimidazolium chloride (R = 1.0). c Fast scanning calorimetry heat flow data of ZIF-4, ZIF-8, and ZIF-62 co-melted with benzimidazolium chloride (R = 1.0), showing glass transition temperatures (Tg) in the range of 130-140 °C. The heating rates used for these measurements were 500 K s−1. We note that heat flow data is normalized to the maximum heat flow due to the very small sample sizes (micro or nanogram), making it infeasible to measure sample masses. d Effect of modifier content on the reduced glass transition temperature (\({T}_{g}^{*}={T}_{g}{T}_{g,0}^{-1}\), where Tg is the glass transition of a modified glass and Tg,0 is the glass transition temperature of a pure glass former), shown for all modified ZIF-4 and ZIF-62 glasses of the present study (see Supplementary Table 1) as well as literature data for silicates61. The dashed lines represent guides for the eye based on exponential decay functions. Source data are provided as a Source Data file.
