[Tex/LaTex] Braket size problem

braketsize;

I have a braket term in an equation. The bra size is bigger than the ket size due to a primed item in the bra part. I know that \big function can make ket size bigger and it can match the height but i want to make the bra size smaller: 

\documentclass[phys]    
\begin{document}
    \begin{equation}
      \bra{\vec{q'}}\ket{\vec{q}}
    \end{equation}
\end{document}

Do you have any suggestions ?

Thanks in advance

Best Answer

this is not an answer, but a demonstration of possibilities.

the code shown in the question doesn't exhibit the described result, namely that the left angle bracket is larger than the right one.

edit: since the request was for a smaller set of brakets, i've added examples showing that the shapes used around the q are the smallest default size. to get smaller ones, one has to go to ridiculous lengths, explicitly specifying a different (and inappropriate) size.

\documentclass[12pt]{article}
\usepackage{braket}
\usepackage{amsmath}
\begin{document}
 \begin{equation*}
   \bra{\vec{q'}}\ket{\vec{q}} \quad
   \bra{\vec{a'}}\ket{\vec{a}} \quad
   \bra{a'}\ket{a} \quad
   {\scriptstyle \bra{{\textstyle{a'}}}\ket{\textstyle{a}}}
 \end{equation*}

 \begin{equation*}
   \bra{\vec{q}\,\smash{'}}\ket{\vec{q}\,} \quad
   \bra{\vec{a}\,\smash{'}}\ket{\vec{a}\,}
 \end{equation*}

 \begin{equation*}
   \bra{\vphantom{a}\smash{\vec{q'}}}\ket{\vec{q}\,} \quad
   \bra{\smash{\vec{a'}}}\ket{\vec{a}\,}
 \end{equation*}
\end{document}

enter image description here

note that the coding here isn't good style -- never use multiple adjacent equation environments. and i've also taken liberties with spacing, since it's not really clear what is wanted.

edit:
it has come to my attention (by way of a comment on Increase in bracket sizes due to power symbol) that the physics package also supports the \bra \ket notation, and according to texdoc physics you can apply a * to suppress automatic sizing (see page 6).

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