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arXiv · 2007.13070

Trends in pKa Values for polyprotic carboxylic acids

Shivam Parashar·Prateek K. Jha
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Abstract

In this work we have reported the pKa values for straight chain (without branches) oligomers of Acrylic acid using CBS-QB3 gas phase energies with solvation free energies from CPCM/HF 6-31G(d) and SMD/B3LYP (2df,p). We have found that the negative log of the first acid dissociation constant decreases with the chain length. Within a chain, the microscopic pKa for the COOH groups present at the end of the chain is maximum and minimum for centrally located COOH groups.

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Shivam Parashar, Prateek K. Jha. 2020-07-26. Trends in pKa Values for polyprotic carboxylic acids. https://arxiv.org/abs/2007.13070

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