1 Reply Latest reply: Feb 21, 2013 1:50 PM by Carlotta Shearson RSS

When to use italics for "para" etc.

Phillip Flanders

I know that italics are required when ortho, meta, and para are included as part of a chemical name (e.g. para-methoxyphenol).  However, I'm confused as to whether or not they should be in italics when used outside of chemical names.  In discussing structural affects, I might refer to a "para substituted aniline", or a "para carboxy group", or a "methyl group in the para position", or say that the "cis isomer reacts at a faster rate than the trans isomer."  I own the ACS style guide (3rd ed), but I can't seem to find a good answer to these situations that are not technically part of a chemical name.    Are you always supposed to put these terms in italics and use a hyphen?  I also quickly perused some literature, but I can't seem to find a good rule to follow.

 

Thanks!

  • Re: When to use italics for "para" etc.
    Carlotta Shearson

    Have a look at p. 145 of The ACS Style Guide (3rd ed.). You'll see that positional and configurational descriptors (e.g., "cis," "trans," "erythro") and element symbol locants that would  be italicized as part of a chemical name are shown in Roman type when not used as part of a chemical name. By analogy, I would treat "para" the same way. As far as hyphenation, I would go with "para-substituted aniline" (because "para" modifies only "substituted") but "para carboxy group" (because "para" modifies the unit "carboxy group" not "carboxy"). No hyphens required for "para position" or "cis isomer"; these are syntactically analogous to "red car." Note, however, that ACS style does call for a hyphen in things like "the carbon in the 6-position" (see p. 263).