Take the tour ×  In LyX, what is a quick way to insert
mismatched delimiters in math environment?  I tried typing
\left|\right>, but it is not interpreted automatically.
share|improve this question Better to use $|\psi\rangle$ for
inlines and \left|\psi\right\rangle for stretchy kets. Avoid
using >. –  Mark S. Everitt Mar 14 '12 at 16:32 I don't know
about Lyx, but there's the braket package. –  cgnieder Mar 14
'12 at 16:36 add comment  2 Answers  There are at least three
different ways one can write such brackets, using ERTs or the
LyX GUI.  1. Use \left/\right directly  To be able to write
\left|\right\rangle, you have to use ERTs, which you add with
Insert --> TeX code or Ctrl + L. Add an ERT for the \left|, exit
the ERT, for example by hitting the right arrow key, write the
term that should be within the delimiters, then finally add
another ERT for \right\rangle.  2. Braket  The braket package
mentioned by cgnieder defines eight new commands, \Bra, \Ket,
\Braket and \Set which uses \left and \right to st