# Spacing between letters of multi-letter identifier changes randomly

I use multi-letter identifiers in my thesis, for which I wrote macros, for example:

\newcommand{\spec}{\mathit{Spec}}


In a text, I always refer to these identifiers as:

some words $\spec$ even more words


In some texts however, latex changes the spacing between the letters: The output looks like

"some words S p e c even more words"

"some words Spec even more words".

How do I prevent latex from adding spaces and always output the latter?

EDIT: Here is a minimal example. The spacing on page one is weird, the spacing on page two is correct. Any ideas?

\documentclass[%
twoside=true,
paper=a4,
BCOR=5mm,
footinclude=true,
fontsize=10pt,
titlepage=true,
abstract=off,
parskip=half-,
footsepline,
cleardoublepage=empty,
open=right,
numbers=noenddot,
fleqn,
index=totoc,
listof=totoc,
american
]{scrreprt}

\PassOptionsToPackage{%
drafting,           % timestamp on every page
pdfspacing         % makes use of pdftex’ letter spacing capabilities
}{classicthesis}

\PassOptionsToPackage{american}{babel}
\usepackage{babel}

\usepackage{classicthesis}
\newcommand{\spec}{\mathit{Spec}}
\newcommand{\bb}{\mathit{b}}

\begin{document}

\chapter{$\bb$-conformance}

Some words $\spec$ some more words.
This is very weird $\sd$-semantics behavior and $\sd$-semantics looks really ugly.

\newpage

Some words $\spec$ some more words.
This is normal $\sd$-semantics behavior.

\end{document}

• Minimal example please, ie something we can copy and run on our machines. Nov 25 '13 at 14:30
• are you sure you always include the backslash? if you happen to input $Spec$ instead of $\Spec$, the individual letters would be "spaced out" since they are being treated as individual variables, not as a word. without an actual example to test, it's impossible to be sure. Nov 25 '13 at 14:30
• Thanks, but I always use the backslash. I'm going to build a minimal example (which is kinda difficult because I use a lot of packages).
– Rich
Nov 25 '13 at 15:11
• If I remove the pdfspacing option, I get what you would like to have (don't ask me why, though) Nov 25 '13 at 16:11

It seems to be a bug with classicthesis; it is triggered by \b in the chapter title, when \mathit is used.

This doesn't seem to happen when you use \textit instead of \mathit.

\documentclass[%
twoside=true,
paper=a4,
BCOR=5mm,
footinclude=true,
fontsize=10pt,
titlepage=true,
abstract=off,
%parskip=half-,% <--- PLEASE, DON'T USE THIS
footsepline,
cleardoublepage=empty,
open=right,
numbers=noenddot,
fleqn,
index=totoc,
listof=totoc,
american
]{scrreprt}

\usepackage[american]{babel}
\usepackage[
drafting,
pdfspacing,
]{classicthesis}

\newcommand{\spec}{\textit{Spec}}
\newcommand{\bb}{\textit{b}}

\begin{document}

\chapter{\texorpdfstring{$\bb$}{b}-conformance}

Some words $\spec$ some more words.
This is very weird $\sd$-semantics behavior and
$\sd$-semantics looks really ugly.

Some words $\spec$ some more words.
This is normal $\sd$-semantics behavior.

\end{document}


Note also that b is not uppercased in the title; the \texorpdfstring is used to avoid a spurious warning.

Please, don't use parskip-.

• Thanks! \textit instead of \mathit seems to work, although I have no idea why. The lowercase b in the title is there on purpose, because it is a mathematical variable. Can you explain why I shouldn't use parskip-?
– Rich
Nov 25 '13 at 16:31
• I've no idea, either: I'll try and investigate. You shouldn't use parsnip- because using it is a clear sign of bad typography. Nov 25 '13 at 16:37
• @Rich It seems to be the fault of classicthesis and the bug is triggered by the \mathit in the chapter title. Nov 25 '13 at 16:47
• I think it's a bug in microtype, actually. The same happens with \documentclass{article} \usepackage{microtype} \begin{document} \textls[200]{$\mathit{b}$-conformance} Some words $\mathit{spec}$ some more words. \end{document}. The problem is that during math font setup, LaTeX sets \globaldefs1, with the result that the letterspaced font instance will leak out. I'll have to see what I can do about it. Nov 25 '13 at 17:01
• The following should help (after loading classicthesis): \def\MT@set@lsfont{\MT@exp@two@c\let\font@name\MT@lsfont\global\let\glb@currsize\@empty} (which, alas, will slow down microtype, again). Nov 25 '13 at 17:50