Use quotation marks after "that which is called" and similar phrases?
Solution 1:
Putting quotes around something is called scare quotes. They are only used when:
a) the term is being used in a non-standard way b) to mark off irony
I assume that you are not using "bar" in an ironic context, so it boils down to a question: are you using "bar" in a non-standard way? For example, you wouldn't put quotes around the following:
DNA is sometimes divided into nucleotides.
You would use quotes if you said:
DNA is sometimes divided into "letters."
Because "letter" is a non-standard term in the context of DNA, it needs scare quotes.
Note
If you are trying to emphasize a word/phrase, never use quotes! Use italics instead.
Solution 2:
The solution is to foo, producing what is called a "bar".
The solution is to foo, producing what is called a bar.
According to Three Editors Blog - last rule in the article: You can use either quotes or italics. I would classify the quoted word here words as words. We often use italics for words used as words, but we can also use quotation marks.
Additionally, according to APA Style Blog - paragraph 2: The APA Manual (on p. 105) recommends using italics for the “introduction of a new, technical, or key term or label," adding "(after a term has been used once, do not italicize it).”
Thus, it seems that both may be acceptable but lean toward italics.