Gas-phase concentrations q(x) = n_x∕n_<H> (with n_x (cm⁻³)) for CO, CH₄, TiO and Na. We follow the same colour code like in Fig. 3: blue – nightside (ϕ = 120° … 240°), orange – dayside (ϕ = 60° … 0°… 300°), black-dashed – substellar point (ϕ = 0°), black-dot-dashed – anti-stellar point (ϕ = 180°). The lighter colours indicate the terminator regions: light orange – evening terminator (ϕ = 90°), light blue – morning terminator (ϕ = 270°). The largest differences between day- and nightside appear for the molecular species depicted.