Mastering the ACS Style Guide Book: Formatting Your Reference List

Creating a robust and correctly formatted reference list is a critical aspect of academic and scientific writing. For those in the field of chemistry and related disciplines, adhering to the American Chemical Society (ACS) style is paramount. This guide will walk you through the essential elements of formatting and ordering your reference list according to the ACS Style Guide Book, ensuring clarity, credibility, and adherence to professional standards.

General Guidelines for ACS Reference Lists

The “References” section, as it is titled, begins on a new page at the end of your document. The word “References” should be centered or left-justified at the top of this page. A distinctive feature of ACS style referencing is the use of a hanging indent. This means that in each reference entry, the first line is aligned to the left margin, while subsequent lines are indented. This format enhances readability and clearly separates each source.

Every entry in your reference list needs to contain key components that allow readers to locate the cited sources. These core components are:

• Author or Editor: The individual(s) or entity responsible for the work.
• Publication Date: The year the work was published.
• Publication Information: Details that specify the type of source and where it can be found (e.g., article title, journal title, book title).

Ordering Your ACS Reference List

The method of ordering your reference list depends on the citation style used within the body of your paper. ACS style employs two primary in-text citation methods: numerical and author-date.

Numerical Citations

If you have used numerical citations, either parenthetical (numbers in parentheses) or superscript (numbers raised above the line), your reference list should be ordered numerically. This means the sources are listed in the order they appear in your paper, starting from 1 and continuing sequentially.

Author-Date Citations (Alphabetical Order)

For papers using author-date citations, the reference list is organized alphabetically by the last name of the first author of each source. When alphabetizing, remember the principle “nothing precedes something.” This is illustrated as follows:

Brown, L.
Brownfield, G.
Browning, R.

This rule implies that shorter surnames come before longer ones with the same starting letters.

For specific formatting rules for different types of sources, continue reading below, and remember to consult the ACS Style Guide Book for comprehensive guidance.

Formatting Components in ACS References

Let’s delve into the specifics of formatting each component of your ACS references.

Author

When listing authors, adhere to the following rules:

• Invert all author names: Present the last name first, followed by a comma and then the initials.
• Maintain author order: List authors in the same order as they appear in the original publication.
• Separate names with semicolons: Use semicolons to punctuate between author names in a single entry.

For example:

Dillard, J. P.; Shen, L.; Guastello, D.; Braun, S.; Gutierrez, J.; Johnston, K.; Olbinski, B.

Publication Date

The formatting of the publication date varies based on the type of source:

• Scholarly Journals: For journal articles, the year of publication is crucial and should be in bold.

  Example: Evans, D. A.; Fitch, D. M.; Smith, T. E.; Cee, V. J. Application of Complex Aldol Reactions to the Total Synthesis of Phorboxazole B. J. Am. Chem. Soc. 2000, 122, 10033-10046.

• Nonscientific Magazines and Newspapers: For these sources, provide the exact date, including the day. Abbreviate the month, followed by the day, a comma, the year, another comma, and the page number (if available). Do not bold the year.

  Example: (Jan 2016, 2010, p H1.).

• Books: For books, simply provide the year of publication without bolding it.

Title

The formatting of titles depends on whether you are referencing a journal article or a book:

• Journals:

  • Capitalize the first word and main words of titles and subtitles. Do not use quotation marks or italics for article titles.
  • End the article title component with a period.
  • Italicize the journal title and abbreviate it according to the Chemical Abstracts Service Source Index (CASSI).

  Example: Caruso, R. A.; Caruso, F. Multilayered Titania, Silica, and Laponite Nanoparticle Coatings on Polystyrene Colloidal Templates and Resulting Inorganic Hollow Spheres. Chem. Mater. 2001, 13, 400-409.

• Books:

  • Italicize the full title and subtitle of books.
  • Finish the book title component with a semicolon.

  Example: Morris, R. The Last Sorcerers: The Path from Alchemy to the Periodic Table; Joseph Henry Press: Washington, DC, 2003; pp 145-158.

Publication Information

The publication information provides essential details about where to locate the source. Formatting differs for journals and books:

• Journals, Magazines, and Newspapers:

  • Italicize the volume number, followed by a comma, and then the pagination.
  • If the journal uses issue numbers, include the issue number in parentheses after the volume number, before the comma, and do not italicize it.
  • Provide the complete page range if possible, without commas or spaces in the pagination.

  Examples:

  Caruso, R. A.; Caruso, F. Multilayered Titania, Silica, and Laponite Nanoparticle Coatings on Polystyrene Colloidal Templates and Resulting Inorganic Hollow Spheres. Chem. Mater. 2001, 13, 400-409.

  Mullin, R. Chem. Eng. News 2005, 83 (42), 7.

• Books:

  • Include the publisher’s name, city, and state (for US publications) or city and country (for non-US, unless it is a major world city), and the year of publication.
  • Publisher names are in normal typeface, not italicized, bolded, or abbreviated, and followed by a colon.
  • The place of publication is followed by a comma.
  • The year of publication is in normal typeface and followed by a period at the end of the reference or a semicolon if more information follows (like page numbers as in the example above for books).

  Example: Gould, S. J. The Structure of Evolutionary Theory; Belknap Press: Cambridge, MA, 2002.

Order of Alphabetical References List (Detailed Rules)

When using author-date citations, further rules apply for ordering entries alphabetically:

Order of Works with the Same First Author

• Single-author works: Arrange these chronologically, from earliest to latest.

  Examples:

  Hamilton, F. J. Biochemistry 2003, 42, 78-86.
  Hamilton, F. J. J. Agric. Food Chem. 2004, 52, 1622-1633.

• Same author(s) and same date: Order chronologically as precisely as possible and append lowercase letters (a, b, c, etc.) immediately after the year.

  Examples:

  Hamilton, F. J. J. Agric. Food Chem. 2004a, 52, 1622-1633.
  Hamilton, F. J. J. Org. Chem. 2004b, 69, 298-306.

• Same first author, different co-authors: These entries follow single-author entries and are then ordered chronologically.

  Examples:

  Scarponi, T. M.; Moreno, S. P. Biochemistry 2002, 41, 345-360.
  Scarponi, T. M.; Adams, J. S. J. Pharm. Sci. 2003, 92, 703-712.

Order of Works by Authors with Same Last Name

Alphabetize by the first initial when authors share the same last name.

Example:

Moher, J.
Moher, M., & Feigenson, L.

Order of Works by Group Authors

Alphabetize group authors by the first significant word in their name. Do not abbreviate the group name.

Examples:

Moher, J.
National Institute of Mental Health.
Oliver, M. B.

By following these detailed guidelines, you can ensure your reference lists adhere to the rigorous standards of ACS style, enhancing the professional presentation and credibility of your scientific writing. For comprehensive and definitive rules, always refer to the ACS Style Guide Book.