  The Minimal Supersymmetric Standard Model (MSSM) with explicit CP violation
is studied with the help of the di-photon decay channel of the lightest neutral
Higgs boson. Effects of CP violation, entering via the scalar/pseudo-scalar
mixing at higher order as well as through the Higgs-sfermion-sfermion couplings
at tree-level, are analyzed in the MSSM with and without light sparticles. A
light stop may have a strong impact on the decay width and Branching Ratio (BR)
of the decay process H_1 -> gamma gamma, whereas other light sparticles have
only little influence. In some regions of the MSSM parameter space with large
CP-violating phase phi_mu ~ 90 degrees a light stop can change the BR by more
than 50%.
