Standard calculation problems involving Aspen Plus

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What standards are used for calculating the content and application of Aspen Plus? How to calculate it? I recently conducted some simulations and found that the results obtained using Aspen Plus for enthalpy and entropy values differ from those calculated using elemental standards. For example, for H2O, the standard enthalpy at 298.15 K calculated using standards is 8.357 kJ/kmol, whereas Aspen gives a value of -237,786.1 kJ/kmol. This discrepancy arises because calculating the enthalpy of pure substances requires using their standard formation enthalpies. In Aspen’s property database, I found that the standard formation enthalpy for elemental sulfur is actually 66.2 kcal/mol. As we know, according to the definition of standard enthalpies, the standard formation enthalpy for elements is 0; therefore, the enthalpy and entropy values calculated by Aspen are based on incorrect standards. I would like to know what standards Aspen Plus uses for calculating enthalpy and entropy values How is it calculated? Hope an expert can answer, it’s urgent! ! ! ! I am extremely grateful