  Quantum tunneling is the quantum-mechanical effect where a particle tunnels
through a classically forbidden region. Double Square Well Potential (DSWP) is
a system where this phenomenon is feasible. Numerous phenomena can be
illustrated by considering motion in a pair of wells that are separated by a
barrier of finite height and width. The energy level splitting, resulting from
barrier penetration, is the reason of the so-called inversion spectrum, which
is an example of quantum tunneling. Out of several molecules ($NH_3$, $PH_3$,
$AsH_3$, $NH_2CN$) where this inversion phenomenon occurs, ammonia molecule
$NH_3$ provides a nice physical realization of a vibrational system with a
DSWP. The main goal of the present work is to examine the implications of
quantum tunneling on information entropy measures (Shannon's and Fisher's) and
statistical complexity.
