𝑣 (the dual descriptor) plays a significant role within the theory of nuclear reactivity indices. It also represents the third energy derivative and has been calculated by the finite difference method applied to the lower order derivatives. 𝑓 (𝐫) has been tested in many chemical applications ever since. Another work by Cardenas et al. provided formal arguments for application of the dual descriptor as the useful tool for predicting the regioselectivity and nucleophilic attack simultaneously. Better predictive power of the softness/hypersoftness over FF/dual index has recently been advocated by Martinez-Araya. The local hypersoftness 𝑠