  A comparison of experimental heavy residue cross sections from the reactions
86Kr+64Ni,112,124Sn with the model of deep-inelastic transfer (DIT) is carried
out. A modified expression for nucleon transfer probabilities is used at
non-overlapping projectile-target configurations, introducing a dependence on
isospin asymmetry at the nuclear periphery. The experimental yields of
neutron-rich nuclei close to the projectile are reproduced better and the trend
deviating from the bulk isospin equilibration is explained. For the
neutron-rich products further from the projectile, originating from hot
quasiprojectiles, the statistical multifragmentation model reproduces the mass
distributions better than the model of sequential binary decay. In the reaction
with proton-rich target 112Sn the nucleon exchange appears to depend on isospin
asymmetry of nuclear periphery only when surface separation is larger than 0.8
fm due to the stronger Coulomb interaction at more compact di-nuclear
configuration.
