Thermodynamic Properties of HFE-7500

_____________Dataset for Thermodynamic Properties of HFE-7500 article_____________ Last updated: 2026-02-03Dataset DOI: 10.5281/zenodo.18481517Article DOI: unavailable ______Contact______* Vojtech Stejfa* stejfav@vscht.cz* +420 220 444 116* ORCID: 0000-0002-2839-8546* Dept. of Physical Chemistry. Faculty of Chemical Engineering, University of Chemistry and Technology, Prague* Technicka 5, 166 28, Prague 6, Czech Republic ______Principal Investigator______* Vojtech Stejfa* stejfav@vscht.cz* +420 220 444 116* ORCID: 0000-0002-2839-8546* Dept. of Physical Chemistry. Faculty of Chemical Engineering, University of Chemistry and Technology, Prague* Technicka 5, 166 28, Prague 6, Czech Republic * Olga Prokopova* prokopova@it.cas.cz* +420 266 053 143* ORCID: 0000-0003-0773-2733* Laboratory of Thermophysical Properties, Institute of Thermomechanics of the Czech Academy of Sciences, Prague* Dolejskova 1402/5, Prague 8, 182 00, Czech Republic * Sebastian Klink* sebastian.klink@mb.tu-chemnitz.de* +49 371 531 39130* ORCID: 0009-0003-5003-7661* Chemnitz University of Technology, Faculty of Mechanical Engineering, Professorship of Applied Thermodynamics* Reichenhainer Strasse 70, 09126 Chemnitz, Germany ______Data manager or custodian______* Vojtech Stejfa* stejfav@vscht.cz* +420 220 444 116* ORCID: 0000-0002-2839-8546* Dept. of Physical Chemistry. Faculty of Chemical Engineering, University of Chemistry and Technology, Prague* Technicka 5, 166 28, Prague 6, Czech Republic ______Licence______*Dataset for article Thermodynamic Properties of HFE-7500 by V. Stejfa, S. Kocian, V. Vins, O. Prokopova, M. Richter and S. Klink is licensed under CC BY 4.0*Licence information: https://creativecommons.org/licenses/by/4.0/------------------------------------------------------------------------------------------------ ______About the dataset______Abstract to be added ThermoML_for_HFE-7500.xml file contains machine-readable data in the ThermoML format, a XML-based IUPAC standard storage and exchange of experimental thermophysical and thermochemical property data. https://www.nist.gov/mml/acmd/trc/thermoml ______Methods of data collection______See the related paper for more information about the measurements.* Phase behaviour (TA2500 Differential Scanning Calorimeter)The phase behavior was investigated at UCT Prague by the heat-flux differential scanning calorimeter (DSC) TA Discovery DSC 2500 (TA Instruments, New Castle, DE, USA) with a cryostat enabling lower limiting temperature of 183 K. The measurements were carried out using the continuous method with a sample size of about 11 mg sealed in hermetic aluminum pan. The calorimeter was periodically calibrated for a range of heating rates with onset temperatures and fusion enthalpies of seven reference materials as described in Pouzar et al. (2025). * Critical properties (TA Q1000 Differential Scanning Calorimeter)The measurements of critical temperature and density were performed at UCT Prague by the heat-flux DSC TA Q1000 (TA Instruments, New Castle, DE, USA) using a continuous method with a heating rate of 10 K min−1. Commercial high-temperature high-pressure stainless-steel pans (TA Instruments, New Castle, DE, USA) with copper washers were used and filled with variable amounts of sample. * Heat capacities (SETARAM Microcalvet Tian-Calvet Calorimeter)Heat-capacity measurements were performed at UCT Prague using a Tian-Calvet calorimeter (SETARAM Microcalvet, Caluire, France) with the operating temperature range 235–355 K. The continuous heating method with a rate of 0.4 K min−1 was used and evaluated in a three-step methodology (identical runs performed with the sample, the reference material, and empty cell (so-called blank experiment)). Synthetic sapphire, NIST standard reference material No. 720, was used as the reference material. The volume of the calorimetric cell of 1.015 ml was determined by filling it with distilled water. The calorimeter calibration and methodology was described previously (Štejfa et al., 2024). * Heat capacities (PE8500 Differential Scanning Calorimeter)To extend the heat-capacity measurements, a DSC 8500 (PerkinElmer, Shelton, Connecticut, USA), which is a double furnace power-compensated DSC at UCT Prague, was used. The temperature increment method was used with a step and heating rate of 5 K and 5 K min−1, respectively and evaluated in the three-step methodology. Ex post temperature and enthalpy calibration corrections are not included in the datafiles. * Vapor pressures (STAT6 Static method)The custom-built STAT6 apparatus equipped with capacitance diaphragm gauges (CDG) originally covered a pressure range from 0.1 to 1333 Pa and a temperature range from 233 to 308 K (Fulem et al., 2010). To enable measurement of higher pressures, a new CDG gauge AA06A12TRA Baratron® (MKS Instruments Inc., USA) with an upper pressure limit of 13330 Pa was installed. Additional indirect calibration of the gauge was performed by measuring vapor pressures on n-heptane and toluene with deviations lower than 0.002 psat in the pressure range 1333 to 13330 Pa. Detailed description of the testing measurements will be included in a different publication. * Vapor pressures (Ebulliometry)The second device used was a custom-built precision ebulliometer of the Swietoslawski type designed for measurement of infinite-dilution coefficients Dohnal and Novotná, 1986 which can also be used for vapor-pressure measurements (Čenský et al., 2010). Texas Instruments quartz pressure gauge (model 145) was used as a pressure sensor and the pressure controller at the same time. The direct calibration of the gauge showed deviations lower than 25 Pa and stability of the pressure (half of maximum amplitude) during the experiments was better than 16 Pa. Together, the standard uncertainty of pressure measurement is evaluated as u(p) = 30 Pa. The boiling temperature was monitored by a secondary reference thermistor silicon-bead probe Hart 5611A (Fluke, USA) in a four-wire connection. The calibration of the thermistor was performed by comparison with a Thermometrics temperature standard (Amphenol ES215) by the manufacturer and was traceable to ITS-90 Preston-Thomas, 1990 and NIST. Standard uncertainty of temperature measurement with the thermistor was u(T) = 0.010 K. The ebulliometer performance was tested by measuring vapor pressures of demineralized water (Millipore RQ unit), toluene, and acetone. * Purity determination (Gas Chomaptography)Chromatograph Hewlett–Packard 6890 equipped with a column HP-1, length 25 m, film thickness 0.52 μm, diameter 0.30 mm, and FID detector. Two determinations for each sample. * Conformer search (CREST calculations)Conformer search was performed (i) using enumeration rules and (i) using the CREST 2.10 algorithm (Pracht et al., 2020) with the following settings: energy window Ewin = 100.0 kcal mol−1 (412 kJ mol−1) and cartesian RMSD threshold rthr = 0.175 Å. * Molecular structure optimizations (Gaussian)Optimizations of stable conformers, vibrational frequencies calculations and potential energy scans were carried out at the B3LYP-D3/6-311+G(2df,p) level of theory with empirical D3 dispersion correction (Grimme et al., 2010) in Gaussian 16 software (Frisch et al., 2016). * Statistical thermodynamics calculationsThermodynamic properties of each conformer were calculated by RRHO model with a 1-DHR corrections for terminal rotations. The calculated fundamental harmonic frequencies were scaled by a double-linear scaling factor: (0.9972 − 1.48·10−5ν/cm−1) for frequencies below 2000 cm−1 and 0.960 above, developed on experimental vibrational frequencies of n-alkanes (Štejfa et al., 2019). * Liquid density (DMA HP Vibrating tube densimeter)The liquid density was measured at IT-CAS with commercial vibrating tube densimeter (VTD) equipped with in-house developed ancillary fluid-handling and pressure-control setups, comprising devices for filling and pressure adjustment and units for temperature control and recording. DMA HP densimeter (Anton Paar, Austria) is capable of measurements from ambient pressure to 70 MPa over the temperature range from 263 to 473 K. Temperature and pressure were read externally with the Pt100 thermometer Omega PR-10-3-100-M30-50-E-2M (ASL F500 bridge) and Omega PX01S1-10KG transducer (Keysight 34970A DAQ), respectively. * Liquid Density (DMA HPM Vibrating tube densimeter)The density was investigated at TUC using a vibrating tube densimeter (Anton Paar DMA HPM) where the oscillation period was measured. Temperature was controlled using a thermostat bath (Huber KISS K15). For temperature measurement a PT100 (Fluke 5618B) together with a resistance bridge (Fluke 1586A super DAQ) was utilized. The pressure was investigated using a pressure transducer Keller PAA-33X. * Speed of Sound (Pulse Echo technique)The speed of sound was investigated at TUC using the double path pulse echo technique with a custom made cell. The acoustic signal was initiated using a Keysight 33500B waveform generator. The receiving signal is recorded using a Keysight DSOX2012A Oscilloscope. Temperature was controlled using a thermostat bath (Huber KISS K15). For temperature measurement a PT100 (Fluke 5606) together with a resistance bridge (Fluke 1586A super DAQ) was utilized. The pressure was investigated using a pressure transducer Keller PAA-33X. ______Methods of data processing______The dataset contains only raw data; no processing is described. ------------------------------------------------------------------------------------------------ ______File name structure, formats, and units_____ * Phase behaviour (TA2500 Differential Scanning Calorimeter) File name AAxxx BBBBBB (z) AAxxx – Experiment series and number BBBBBB – sample identification z – run number (all runs are executed with the same loading) File format: plain text, txt (UTF-8 encoded) Method details metadata are included in the file. Units are include