  We have studied the conformational and scaling behaviors of a flexible
dendrimer immersed in athermal or good solvents. A self-consistent field theory
combined with a pre-averaged excluded volume potential representing the
two-body short-ranged interaction between the segments, was adopted to
calculate the density profile of various generations and branch points
thoroughly. Our calculation results support the "dense-core" model. We find the
conformation of the dendrimer is strongly stretched in the dense central
region, but much weakly stretched in the outer region where the segment density
profile is shoulder shaped. Both our self-consistent field theory calculation
and the Flory mean-field theory calculation give the same scaling law R
proportional to (GP)^0.2N^0.4, where G is the generation number of the
dendrimer, P is the spacer segment number, and N is the total segment number.
If we fix G, the scaling law is simplified to R proportional to P^0.6 in good
solvent.
