Erratum: The effects of nitroxide structure upon 1H Overhauser dynamic nuclear polarization efficacy at ultralow-field (Journal of Chemical Physics (2021) 155 (144203) DOI: 10.1063/5.0064342)

Abstract

In the original article,1 we present characteristic parameters of the Overhauser dynamic nuclear polarization (ODNP)-efficacy of 27 nitroxide radical samples. A typing error in a MATLAB-script led to an incorrect scaling factor, affecting the parameters Emax, P1/2, and ζ • smax. Emaxand ζ • smaxhave to be increased by a factor of ∼1.5 compared to the previously presented values, while P1/2 is only slightly affected (∼3% change). Due to limited RF-power, the fit model did not converge for compounds B1 and B2. Only a lower bound for the corresponding parameters could be estimated. A quantitative inspection of the corrected values reveals that the losses in our setup/samples are much lower than previously assumed. The agreement of the corrected Emax values with calculations described in the literature2,3is improved after revision. Since all values for these parameters are equally affected, the qualitative analysis, discussion, and conclusion of the publication remain valid. The following list specifies the passages of the original article that contain erroneous values, along with the respective corrections. The revised versions of Tables I and II and Fig. 2 of the original publication are presented below. (i) On p. 5 (section titled RESULTS AND DISCUSSION), regarding compound M6dn, “(Emax = −126.2)” must be replaced by “(Emax = −191.1).” (ii) On p. 5 (section titled RESULTS AND DISCUSSION), regarding TEMPO (M4), “∣Emax∣ of 101.9” must be replaced by “∣Emax∣ of 153.7.” (iii) On p. 5 (section titled RESULTS AND DISCUSSION), regarding PCA (M7), “P1/2 of 5.3 W” must be replaced by “P1/2 of 5.4 W.” (iv) On p. 6 (section titled Neighboring substituents to the nitroxide group), the sentence “Only E4 (P1/2 = 6.2 W) has a lower P1/2 than M6 (P1/2 = 7.1 W).” must be replaced by “Only E4 (P1/2 = 6.4 W) has a lower P1/2 than M6 (P1/2 = 7.2 W).” (v) On P. 6 (section titled Neighboring substituents to the nitroxide group), the passage “P1/2 = 4.8 W of C1[⋅⋅⋅]” must be replaced with “P1/2 = 4.9Wof C1[⋅⋅⋅].”