Correction to: Nature Chemistry https://doi.org/10.1038/s41557-021-00713-2, published online 3 June 2021

In the version of this Article initially published, a typo appeared in reference to Sondheimer in the second sentence of the third paragraph, and in Fig. 1a panel and caption. Additionally, the following text was missing from the end of the Acknowledgements section: “The MAS-DNP instrument at NHMFL is supported by the NIH P41 GM122698 and NIH S10 OD018519 grants.”

These changes have been made to the online version of this Article.