  We consider the color suppressed (nonfactorizable) amplitude for the decay
mode $\bar{B_{d}^0} \rightarrow \pi^0 \pi^{0} $. We treat the $b$-quark in the
heavy quark limit and the energetic light ($u,d,s$) quarks within a variant of
Large Energy Effective Theory combined with an extension of chiral quark
models. Our calculated amplitude for $\bar{B_{d}^0} \rightarrow \pi^0 \pi^{0} $
is suppressed by a factor of order $\Lambda_{QCD}/m_b$ with respect to the
factorized amplitude, as it should according to QCD-factorization. Further, for
reasonable values of the (model dependent) gluon condensate and the constituent
quark mass, the calculated nonfactorizable amplitude for $\bar{B_{d}^0}
\rightarrow \pi^0 \pi^{0} $ can easily accomodate the experimental value.
Unfortunately, the color suppressed amplitude is very sensitive to the values
of these model dependent parameters. Therefore fine-tuning is necessary in
order to obtain an amplitude compatible with the experimental result for
$\bar{B_{d}^0} \rightarrow \pi^0 \pi^{0} $.
