Creating an energy level diagram, I used this answer to make the node circles equal radius: How to set exact radius for a node?
\documentclass{report}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\node[circle,draw,blue,text width=0.3cm,text height=0.3cm] at (5,9) {$\uparrow$};% 4d
\node[circle,draw,blue,text width=0.3cm,text height=0.3cm] at (6,9) {$\uparrow$};% 4d
\node[circle,draw,blue,text width=0.3cm,text height=0.3cm] at (7,9) {};% 4d
\node[circle,draw,blue,text width=0.3cm,text height=0.3cm] at (8,9) {\phantom{6}};% 4d
\node[circle,draw,blue,text width=0.3cm,text height=0.3cm] at (9,9) {\quad};% 4d
\end{tikzpicture}
\end{document}
But the empty nodes are still ever so slightly smaller than the filled ones! Tried including phantom or quad to no avail.
What am I missing?
