![Author ORCID: We display the ORCID iD icon alongside authors names on our website to acknowledge that the ORCiD has been authenticated when entered by the user. To view the users ORCiD record click the icon. [opens in a new tab]](https://chemrxiv.org/engage/assets/public/chemrxiv/images/logos/orcid.png)
Abstract
The following article has been submitted to The Journal of Chemical Physics. After it is published, it will be found at https://aip.scitation.org/journal/jcp .
In this work, we investigate how uncertainties in experimental input data influence the results of quantum cluster equilibrium calculations.
In particular, we focus on the calculation of vaporization enthalpies and entropies of seven organic liquids, compare two computational approaches for their calculation and investigate how these properties are affected by changes in the experimental input data.
It is observed that the vaporization enthalpies and entropies show a smooth dependence on changes in the reference density and boiling point.
The reference density is found to have only a small influence of the vaporization thermodynamics, whereas the boiling point has a large influence on the vaporization enthalpy but only a small influence on the vaporization entropy.
Furthermore we employed the Gauss--Hermite estimator in order to quantify the error in the thermodynamic functions that stems from uncertainties in the experimental reference data at the example of the vaporization enthalpy of (R)-butan-2-ol.
We quantify the error as 30.95 J/mol.
Additionally we compare the convergence behaviour and computational effort of the Gauss--Hermite estimator with the Monte Carlo approach and show the superiority of the former.
By this, we present how uncertainty quantification can be applied to examples from theoretical chemistry.
Supplementary materials
Title
Supporting Information (Tables and Figures)
Description
Additional tables showing the absolute and relative deviations of the calculated enthalpies and entropies of vaporization from the experimentally measured values (Table S1 and S2); additional figures showing the enthalpy of vaporization plotted against the experimental input density and boiling point (Fig. S1 to S5); additional figures showing the entropy of vaporization plotted against the experimental input density and boiling point (Fig. S6 to S10); additional figures showing the cluster populations depending on the chosen reference values (Fig. S11 to S15); additional figure showing all the cluster populations of (R)-butan-2-ol depending on the chosen reference values (Fig. S16); additional tables showing all empirical parameters a_mf and b_xv for all investigated systems with increased/decreased densities and boiling points (Table S3 and S4); additional tables showing the relative cluster binding energies of all clusters used in this work (Table S5 to S7).
Actions
Title
Input geometries and frequencies
Description
Geometries (.xyz files) and frequencies (.flist files) for all clusters used in this work.
Actions
