Replacement of the phosphodiester linkages of the polyanion RNA with guanidinium linkers provides the polycation ribonucleic guanidine (RNG). Molecular dynamics studies to 1080 ps of the hybrid duplex formed from an octameric RNG strand r(Ag)(8) with a complementary DNA oligomer strand d(Tp)(8) have been carried out with explicit water solvent and Na+Cl- counterions under periodic boundary conditions with use of the CHARMM force field and Ewald summation method. The Watson-Crick hydrogen bonding pattern of the A/T tracts was maintained intact through the simulation without any structural restraints. Even for the two ends, only one end was partially frayed, The overall structure is equilibrated at a B-DNA conformation, and the RNG strand takes on the general conformation of the DNA backbone. The structural history of the RNG . DNA duplex was determined by examining histograms from the dynamics run. The histograms are of the hydrogen bonding pattern (sequence recognition) and base pair opening occurrences, minor groove width narrowing (3 Angstrom), and bending of tracts. The bending angle measured between the local axis vectors of the first and last helical axis segments is about 33 degrees for the averaged structure. Propeller twist (associated with three-centered hydrogen bonding) up to -30 degrees, native to DNA AT base pairing, was also observed. The sugar pseudorotation phase angles and the ring rotation angles for the DNA strand are within the C3’-endo domain. However, for the RNG strand the pseudorotation angles converted to O4’-endo.