  Generally, when imaginary part of an optical potential is non-symmetric the
reflectivity, $R(E)$, shows left/right handedness, further if it is not
negative-definite the reflection and transmission, $T(E)$, coefficients become
anomalous in some energy intervals and absorption is indefinite ($\pm$). We
find that the complex PT-symmetric potentials could be exceptional in this
regard. They may act effectively like an absorptive potential for any incident
energy provided the particle enters from the preferred (absorptive) side.
