Supernonlinear ion-acoustic waves (IAWs) and their multistability are studied under the Zakharov-Kuznetsov (ZK) and modified ZK (mZK) equations in a rotating magnetized electron-ion plasma that consists of generalized (r, q)-distributed electrons. Bifurcation of IAW is presented through phase plane analysis and existence of IAW solutions is also shown through graphs of potential energy function. Supernonlinear wave exists for system corresponding to mZK equation with nonlinear periodic and solitary wave solutions. Effects of strength (q) and flatness (r) of the (r, q)-distribution on IAW solutions are shown along with other parameters, such as speed of the wave (V ) and direction cosine (n). Furthermore, introducing an extraneous periodic perturbation, multistability property of the perturbed dynamical system is examined, and it is displayed using phase space and time series plots. Features of coexisting trajectories are examined for different values of spectral indices (r, q). Existence of two different types of chaos are supported through Lyapunov exponent graphs. Here acceptable parametric values of spectral indices (r, q) are considered from data values of slow solar wind streams. Hence, supernonlinear periodic IAW and multistability property under the modified ZK equation are reported for the first time in rotating electron-ion magnetized plasma with (r, q)distributed electrons. This study is applicable to understand supernonlinear wave features and multistability property of ion-acoustic wave motions featured in slow solar wind streams.
