ACS Reference List Formatting

ACS Reference List Basics

The reference list is the numbered compilation of citations supporting your in-text references. In ACS style, this list appears at the end of your document and is numbered sequentially in the order sources first appear in your text. This organization differs from alphabetical systems and follows the logical progression of your scientific argument.

Each ACS reference contains specific elements in a particular order: authors, abbreviated journal title, year, volume, and page numbers. The precise formatting of these elements is critical for professional presentation in chemistry research.

General Reference Format Structure

The basic structure for most ACS references follows this pattern:

Number. Author(s); Journal Abbreviation Year, Volume, page.

Key formatting elements include:

• Reference number: Followed by a period
• Authors: Initials followed by surname, separated by semicolons
• Journal title: Abbreviated according to Chemical Abstracts Service abbreviations
• Year: In bold (when formatting allows)
• Volume: In bold
• Page numbers: Actual page range

Author Name Formatting

Authors in ACS references appear with initials first, followed by surname:

Smith, J. A.; Johnson, B. C.; Williams, D. D.

For multiple authors, separate with semicolons. All authors are typically listed (unlike some styles that limit author listings).

Example:

Smith, J. A.; Johnson, B. C.; Williams, D. D.; Anderson, M. L.; Peterson, R. L.; Thompson, J. K.

Journal Article References

Journal article citations are the most common type in chemistry literature. The format includes:

Number. Author(s); Journal Abbreviation Year, Volume, page.

Example:

1. Chen, L.; Rodriguez, M.; Thompson, K. Effectiveness of Novel Synthesis Methods. J. Org. Chem. 2025, 90, 1234–1243.

Notice that:

• The journal title is abbreviated (from Chemical Abstracts)
• The year appears in bold or plain text
• The volume number appears in bold
• Pages are listed with an en-dash

Chemical Abstracts Service Journal Abbreviations

ACS requires specific journal abbreviations from Chemical Abstracts. Common examples:

• J. Am. Chem. Soc. = Journal of the American Chemical Society
• J. Org. Chem. = Journal of Organic Chemistry
• Angew. Chem., Int. Ed. = Angewandte Chemie International Edition
• Tetrahedron Lett. = Tetrahedron Letters
• J. Med. Chem. = Journal of Medicinal Chemistry
• Chem. Rev. = Chemical Reviews
• Anal. Chem. = Analytical Chemistry
• Inorg. Chem. = Inorganic Chemistry
• Biochemistry = Biochemistry

These abbreviations must be exact and can be found in the Chemical Abstracts Service Source Index.

Volume and Issue Numbers

ACS citations typically use volume numbers in bold:

**2025**, 90, 1234–1243.

Issue numbers are usually omitted in ACS format, unlike some other scientific styles.

Page Numbers and En-dashes

Always include complete page ranges with en-dashes (not hyphens):

1234–1243 (correct, using en-dash)
1234-1243 (incorrect, using hyphen)

DOI and Online Publication Information

Include Digital Object Identifier when available:

1. Smith, J. A.; Johnson, B. C. Article Title. J. Chem. Res. 2025, 90, 1234–1243. DOI: 10.1234/jcr.2025.001

For online-only journals:

2. Johnson, B. C.; Williams, D. D. Article Title. J. Virtual Chem. 2025, 162, article ID 124504. DOI: 10.1234/jvc.2025.123

Book References

Books follow a slightly different format:

Number. Author(s); Book Title; Publisher: Location, Year; pp XXX–XXX.

Example:

3. Martinez, R.; Patterson, S. Organic Synthesis Strategies; Elsevier: Amsterdam, 2025; pp 234–256.

Elements include:

• Full author names
• Book title (italicized in some formats)
• Publisher name and location
• Publication year
• Page numbers (when citing specific chapters)

Edited Book Chapters

For chapters in edited collections:

Number. Chapter Author(s); Chapter Title. In Book Title; Editor Name(s), Ed(s).; Publisher: Location, Year; pp XXX–XXX.

Example:

4. Thompson, J. K.; Anderson, M. L. Catalytic Reactions. In Advanced Organic Chemistry; Williams, D. D., Ed.; Springer: Berlin, 2025; pp 156–189.

Electronic and Online Books

For e-books and online resources:

5. Peterson, R. L.; Anderson, J. K. Digital Chemistry Resources. In Electronic Laboratory Manual; Smith, J. A., Ed.; Cambridge University Press: Cambridge, UK, 2025; https://www.cambridgeuniversitypress.edu (accessed Date).

Website and Online Resource Citations

For web-based resources:

6. National Center for Biotechnology Information. Chemistry Database. https://www.ncbi.nlm.nih.gov/chemistry (accessed Mar 10, 2026).

Or for organizational websites:

7. American Chemical Society. Chemical Safety Database. https://www.acs.org/safety (accessed Mar 12, 2026).

Conference Proceedings

For conference papers:

8. Martinez, R.; Patterson, S. Novel Synthetic Approaches. In Proceedings of the American Chemical Society Meeting; Chicago, IL, March 14–18, 2025; paper 234.

Dissertation and Thesis Citations

For unpublished academic work:

9. Anderson, J. K. Novel Approaches to Organic Synthesis. Ph.D. Dissertation, University of California, Berkeley, 2025.

Unpublished Manuscripts

For work submitted but not yet published:

10. Johnson, B. C.; Williams, D. D. Article Title. Submitted for publication in J. Org. Chem. 2025.

Patents

Patent citations follow specific format:

11. Smith, J. A.; Johnson, B. C. Method for Organic Synthesis. U.S. Patent 10,123,456 B2, June 15, 2025.

Supplementary Materials and Data

When citing supplementary online materials:

12. Peterson, R. L.; Thompson, J. K. Extended Spectroscopic Data. Supporting Information for [Reference Article]. https://doi.org/10.1234/journal.2025.045 (accessed Mar 15, 2026).

Software and Computational Resources

For software citations:

13. GAUSSIAN 16, Revision C.01; Gaussian, Inc.: Wallingford, CT, 2019.

Chemical Database Citations

For online chemical databases:

14. PubChem Database. CID=10497, https://pubchem.ncbi.nlm.nih.gov/compound/10497 (accessed Mar 10, 2026).

Using GenText for Reference List Management

GenText streamlines ACS reference list creation by automatically formatting references according to ACS guidelines, managing Chemical Abstracts journal abbreviations, correctly formatting author names and punctuation, and checking for consistency across your document.

Organizing Your Reference List

Arrange references in the order they first appear in your text:

1. First cited source
2. Second cited source
3. Third cited source

This sequential arrangement helps readers track your scientific logic and find references quickly.

Special Citation Situations

Accessed vs. Published Dates: For online content, include both when available. The accessed date shows when you retrieved the information.

Chemical Compound Identifiers: Include CAS numbers when helpful for identifying compounds:

Smith, J. A.; Johnson, B. C. Synthesis of Benzene (CAS 71-43-2). J. Org. Chem. 2025, 90, 1234.

Missing Information: If publication information is unavailable, note it clearly:

[publisher unknown]; 2025

Formatting Consistency Checklist

Before finalizing your reference list:

• Verify all author names are correctly spelled
• Check that journal titles are properly abbreviated per CAS standards
• Confirm page numbers are complete and use en-dashes
• Ensure all reference numbers match in-text citations
• Review punctuation placement throughout (periods, semicolons)
• Verify that italicized elements are properly formatted
• Check DOI formatting consistency

Common Reference List Errors

Error 1: Using full journal names instead of abbreviations Incorrect: Journal of Organic Chemistry Correct: J. Org. Chem.

Error 2: Using hyphens instead of en-dashes for page ranges Incorrect: 234-245 Correct: 234–245

Error 3: Inconsistent author name formatting or author count

Error 4: Mismatched reference numbers between text and list

Conclusion

Proper ACS reference list formatting demonstrates professionalism and enables readers to access and verify your sources. By understanding the structure and rules for different source types, and utilizing tools like GenText to manage formatting details, you ensure your references meet ACS standards. This attention to citation detail reflects your commitment to scientific integrity and contributes to the reliability of chemical literature.