\toprule
    \backslashbox{$x_{Toluene} [-]$}{T [\si{\celsius}]} & x_toluene: & 5 & 15 & 25 & 35 & 45 \\ 
\midrule 
    0.05 & 3.33 & 3.23 & 3.17 & 3.12 & 3.1 \\ 
    0.25 & 4.38 & 4.19 & 3.98 & 3.85 & 3.74 \\ 
    0.5 & 5.63 & 5.26 & 4.92 & 4.64 & 4.41 \\ 
    0.75 & 6.63 & 6.1 & 5.56 & 5.2 & 4.86 \\ 
    0.95 & 7.2 & 6.54 & 5.96 & 5.53 & 5.15 \\ 
\bottomrule