Normalized Spitzer transit depth difference as a function of the equilibrium temperature for the complete grids of transmission models created with our atmospheric model framework describedin Sects. 3.2.3 and 3.2.4. At each temperature, we show the models where the surface gravity is representative of our survey; i.e., at T_eq > 1800 K we only plot g = 1500 and 5000 cm s⁻². Panels from left to right show equilibrium chemistry (no vertical mixing), K_zz = 10⁸, K_zz = 10¹⁰ and K_zz = 10¹² cm² s⁻¹. The bluetranslucent shaded region shows the 1x solar composition and orange translucent shaded region shows the 30x solar composition (overlap in purple). Gray dashed line represents a gray opacity source showing no spectral features. Planets from our sample are overplotted in purple circles with their 1σ error bars.