Diagonal text in diagonal matrix

I have a tridiagonal matrix whose diagonals d_{-1}, d_0, d_1 (thought as vectors) can be written as vector expressions.

Is there a way to nicely represent this, e.g. via a matrix which is blank everywhere except from the diagonals which report the expression (written diagonally) and maybe continuous lines elsewhere?

Any help appreciated.

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Did you try this by setting up a matrix of math nodes in Tikz? I'll try and see how it goes for me... –  kan Apr 11 '13 at 17:20

\documentclass{article}
$\left( \rotatebox[origin=c]{-45}{\begin{tabular}{c} \rule[.5ex]{3em}{.5pt} \exp_1(C) \rule[.5ex]{3em}{.5pt}\\ \rule[.5ex]{4em}{.5pt} \exp_0(C) \rule[.5ex]{4em}{.5pt}\\ \rule[.5ex]{3em}{.5pt} \exp_{-1}(C) \rule[.5ex]{3em}{.5pt} \end{tabular}} \right)$