My paper contains many math expressions like $abcde$ or $abdefv$. Unfortunately, the latter looks very ugly, particularly in regards to the spacing around the f. In particular, there is a significant amount of space around the f which is not present around the other letters.

Is there a method to make that spacing tighter?

Note: Joseph Wright suggested using \! to get a negative thin space. This does seem to help. But I'm still a bit curious as to why the problem occurs at all. For example, it looks fine in $acdfv$ before the f but not after. If anyone has some more details on why the spacing ends up as it does, please comment. Thanks.

  • 1
    Seems like a very unlikely product - do you really mean this? If so, perhaps try \! to back the spacing up.
    – Joseph Wright
    Dec 9, 2010 at 17:30
  • @Joseph Wright: Yes, that's an actual example from my paper, but $efv$ has the same problem and isn't as unlikely. Thanks for the $\!$ advice -- I guess I should have thought about that. That works before the $f$ quite well. Is there a predefined way to get an even thinner negative space (for after the $f$) or should I use $\hspace{-..}$?
    – A. Rex
    Dec 9, 2010 at 17:38
  • 2
    Sounds like tensor calculus, which leads to, as Spivak calls it in his differential geometry tome, "The debauch of indicies." Dec 9, 2010 at 19:44

2 Answers 2


For a detailed answer why this is happening you can read this answer of mine (shameless plug indeed): In short, the italic correction of the f has a great part in this. But the italic correction only explains the spacing after the f, not before. For this you have to look at the bounding boxes of the letters:

The first f is a text italic letter in its bounding box, the second one is math italic (in its bounding box together with its italic correction). As you can see, the text letter protrudes a bit to the left (and a lot to the right); the math letter has a tiny bit of white space in the left (and also in the right, because of the italic correction). For a bit more about the bounding boxes see this question of mine (another shameless plug :-)).

I first noticed the problem when typing $Vf$, which doesn't yield a nice output. My resort is using $V\hspace{-0.1em}f$ instead (in a macro, of course), which I like much better. You could even use $V\!f$, but this I find too narrow. Compare these three:


I would not encourage you to follow Caramdir's (now removed) suggestion to use $\mathit{Vf}$ since this uses a different font (text italic, not math italic). You can see quite clearly that the V is narrower (in other words, the angle at the bottom of the V is more acute):

If you use a different math font (like Euler), then the difference is even more noticeable.

(For a case where \textit could be a good solution, see this answer of TH.)


Math mode considers each symbol a separate variable, not part of a "word". If you want word-like behaviour, use \mathrm{...} or \mathit{...}. If this really is a product, perhaps using \cdot between factors (or reorganizing, or changing variable names, perhaps distinguished by subindices) helps.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .