Heat capacities and thermodynamic properties of MgNDC

Abstract

One-three-dimensional metal-organic frameworks Mg 1.5 (C 12 H 6 O 4 ) 1.5 (C 3 H 7 NO) 2 (MgNDC) has been synthesized solvothermally and characterized by single crystal XRD, powder XRD, FT-IR spectra. The low-temperature molar heat capacities of MgNDC were measured by temperature modulated differential scanning calorimetry (TMDSC) over the temperature range from 205 to 470 K for the first time. No phase transition or thermal anomaly was observed in the experimental temperature range. The thermodynamic parameters of MgNDC such as entropy and enthalpy relative to reference temperature of 298.15 K were derived based on the above molar heat capacities data. Moreover, the thermal stability and decomposition of MgNDC was further investigated through thermogravimetry (TG)-mass spectrometer (MS). Three stages of mass loss were observed in the TG curve. TG-MS curve indicated that the oxidative degradation products of MgNDC are mainly H 2 O, CO 2 , NO, and NO 2 .

Heat capacities and thermodynamic properties of Co(3,5-PDC)(H2O)

“…The heat capacity calibration, similar to our previous publication [16][17][18][19] The masses of the reference and sample pans with lids were both measured to be within 56.75 ± 0.05 mg. Samples were crimped in non-hermetic aluminum pans with lids.…”

Determination of heat capacities and thermodynamic properties of two structurally unrelated but isotypic calcium and manganese(II) 2,6-naphthalene dicarboxylate-based MOFs

“…Through the polynomial representing heat Besides the fundamental and practical importance in compiling various thermodynamic parameters (here C p,m , DH and DS) and their variation with temperature for the two compounds investigated in this study, we have compared the present values with those obtained by our group using the same experimental methods for three other MOFtype materials based on NDC and optionally DMF in their structure, namely Li 2 (2,6-NDC) [24], Li 2 (1,4-NDC)(DMF) [26], and Mg(2,6-NDC)(DMF) 0.66 [31]. While the C p,m , DH and DS values are relatively close for the above studied Ca and Mn compounds, the same parameters for the other three samples give markedly different and random values, confirming that their thermodynamic parameters are rather related to the structure of the compounds than to the nature of their constituents.…”

“…A mechanical cooling system was used for the experimental measurement. The temperature scale of the instrument was initially calibrated in the standard DSC mode, using the extrapolated onset temperatures of the melting of indium (429.75 K), as described in our previous articles [27][28][29][30][31][32]. The energy scale was calibrated with the heat of fusion of indium (28.45 J g -1 ).…”

“…This method has been extensively developed for a straightforward determination of heat capacities for various MOF-type materials, isothermally and non-isothermally [27][28][29][30][31][32].…”

Heat capacities and thermodynamic properties of a 3D Cu(II) supramolecular complex

“…As described in our previous studies [23][24][25], the heat capacity calibration was made by running a standard sapphire (a-Al 2 O 3 ) at the experimental temperature. The calibration method and the experiment were performed at the same conditions as follows: (1) sampling interval: 1.00 s/pt; (2) zero heat flow at 428.15 K; (3) equilibrate at 183.15 K; (4) isothermal for 5.00 min; (5) temperature ramp at 10 K min -1 to 673.15 K. The masses of the reference and sample pans with lids were measured to be within 56.75 ± 0.05 mg.…”