  This paper presents surface photometry (B,V, I, J, H, K) and H_alpha rotation
curves of 27 isolated spiral galaxies. The final goal is to obtain the mass
distribution of a sample of isolated spiral galaxies in order to model their
gas kinematics. This is then compared to the observed rotation curve, to
determine the necessity of a dark halo in the inner parts (Perez et al. 2004).
The azimuthally averaged radial surface brightness profiles and the integrated
magnitudes obtained from ellipse fitting are given for each of the sample
galaxies. The ellipse fitting technique applied to the light distribution also
allowed us to obtain the size of the bar, and the inclination and position
angle of the outer isophotes that allow the galaxy deprojection. Using these
profiles, 1-D disk-bulge decomposition was performed to obtain the disk
scale-length and the bulge effective radius for the different bands. Through
the fitting of a parametric function to the observed rotation curve, the
maximum rotational velocity and the corresponding radius was obtained. The
correlation between the bulge and disk parameters is in agreement with previous
studies (de Jong 1996a; Marquez & Moles 1999; Baggett et al. 1998). Regarding
the Kormendy relation (Kormendy 1977), in agreement with de Jong, no
correlation between the bulge effective radius and its surface brightness is
found, possibly due to the small range of bulge magnitudes covered. We find a
smaller scatter in the structural relations when compared to non-isolated
samples in agreement with Marquez & Moles (1999). Finally, a correlation
between the disk scale-length and the bar size is observed, possibly reflecting
the rapid growth of a bar.
