Adiabatic index, Γ, as a function of radial coordinate within power-law and square-root exponential models of ﹩f({ \mathcal R },{{ \mathcal L }}_{m})﹩ gravity. The solid black line denotes the GR, while the colored lines represent the different values of σ and γ. Here, the purple dashed line represents Γ = 4/3 below which a stellar object will be unstable