  Optical phase curves have become one of the common probes of exoplanetary
atmospheres, but the information they encode has not been fully elucidated.
Building on a diverse body of work, we upgrade the Flexible Modeling System
(FMS) to include scattering in the two-stream, dual-band approximation and
generate plausible, three-dimensional structures of irradiated atmospheres to
study the radiative effects of aerosols or condensates. In the optical, we
treat the scattering of starlight using a generalisation of Beer's law that
allows for a finite Bond albedo to be prescribed. In the infrared, we implement
the two-stream solutions and include scattering via an infrared scattering
parameter. We present a suite of four-parameter general circulation models for
Kepler-7b and demonstrate that its climatology is expected to be robust to
variations in optical and infrared scattering. The westward and eastward shifts
of the optical and infrared phase curves, respectively, are shown to be robust
outcomes of the simulations. Assuming micron-sized particles and a simplified
treatment of local brightness, we further show that the peak offset of the
optical phase curve is sensitive to the composition of the aerosols or
condensates. However, to within the measurement uncertainties, we cannot
distinguish between aerosols made of silicates (enstatite or forsterite), iron,
corundum or titanium oxide, based on a comparison to the measured peak offset
($41^\circ \pm 12^\circ$) of the optical phase curve of Kepler-7b. Measuring
high-precision optical phase curves will provide important constraints on the
atmospheres of cloudy exoplanets and reduce degeneracies in interpreting their
infrared spectra.
