When to Use It: Parenthetical numbering is the preferred method of in-text citations in the 2020 ACS Guide to Scholarly Communication. It is used for ACS Style submissions (journals/books) and for the HTML versions of ACS publications because the parenthetical numbers make it easier to click from the an article's full text HTML content to view the full references.
Ex: The mineralization of TCE by a pure culture of a methane-oxidizing organism has been reported (6).
Ex: Equations have been derived to extract kinetic parameters from these voltammomagrams (2,3).
Ex: Other groups have also devised clever ways to utilize this reaction (18-20).
When to Use It: Superscript numbering used to be the most commonly used form of in-text ACS citation so you will still see a lot of articles and examples that use superscript. You may be asked to use superscript numbering to demonstrate that you understand it. It is very similar to parenthetical numbering with a few exceptions.
Crick8 hypothesized ...
Ex: Equations have been derived to extract kinetic parameters from these voltammomagrams.2,3
Ex: Other groups have also devised clever ways to utilize this reaction.18-20
All citation examples are from ACS 4.3.2 Creating References. More examples and specific citation scenarios are also addressed in that section.
Author Last, I. I.; Author 2 Last, I. I. Title of Article. Abbrev. Journ. YEAR, Volume (Issue), Page numbers. DOI: ##.####
Foster, J. C.; Varlas, S.; Couturaud, B.; Coe, J.; O’Reilly, R. K. Getting into Shape: Reflections on a New Generation of Cylindrical Nanostructures’ Self-Assembly Using Polymer Building Block. J. Am. Chem. Soc. 2019, 141 (7), 2742−2753. DOI: 10.1021/jacs.8b08648
1. Brus, L. E. Electron−Electron and Electron−Hole Interactions in Small Semiconductor Crystallites: The Size Dependence of the Lowest Excited Electronic State. J. Chem. Phys. 1984, 80 (9), 4403−4409. DOI: 10.1063/1.447218
2. Empedocles, S. A.; Bawendi, M. G. Quantum-Confined Stark Effect in Single CdSe Nanocrystallite Quantum Dots. Science 1997, 278, 2114−2117. DOI: 10.1126/science.278.5346.2114
3. Bennett, A. J.; Patel, R. B.; Skiba-Szymanska, J.; Nicoll, C. A.; Farrer, I.; Ritchie, D. A.; Shields, A. J. Giant Stark Effect in the Emission of Single Semiconductor Quantum Dots. Appl. Phys. Lett. 2010, 97 (3), 031104. DOI: 10.1063/1.3460912