  In a model of isospin symmetry breaking we obtain the ($e^{-} e^{+}
\rightarrow \pi^{-} \pi^{+}$) amplitude $Q$ and the isospin $I=0$ and $I=1$
relative phase $\psi$ at the $\phi (1020)$ resonance in aproximate agreement
with experiment. The model predicts $\Gamma(\phi \rightarrow \omega \pi^{0})
\approx 4 \cdot 10^{-4} \;\mbox{MeV}$. We have also obtained $\Gamma (\phi
\rightarrow \eta' \gamma)=5.2 \cdot 10^{-4} \;\mbox{MeV}$. Measuring this
partial width would strongly constrain $\eta$-$\eta'$ mixing. The branching
ratios $BR$ of the isospin violating decays $\rho^{+} \rightarrow \pi^{+} \eta$
and $\eta' \rightarrow \rho^{\pm} \pi^{\mp}$ are predicted to be $BR(\rho^{+}
\rightarrow \pi^{+} \eta)=3 \cdot 10^{-5}$ and $BR(\eta' \rightarrow \rho^{\pm}
\pi^{\mp})=4 \cdot 10^{-3}$, respectively, leading to $BR[\phi \rightarrow
\rho^{\pm} \pi^{\mp} \rightarrow (\pi^{\pm} \eta)\pi^{\mp} \rightarrow
(\pi^{\pm} \gamma \gamma)\pi^{\mp}]=10^{-6}$ and $BR[\phi \rightarrow \eta'
\gamma \rightarrow (\rho^{\pm} \pi^{\mp})\gamma]=2\cdot 10^{-6}$.
