Figure 1.
(a) The structure of the duplex DNA d[5′-(G)6-3′]·d[3′-(C)6-5′]. (b) The IP of the DNA oligomer d[5′-(G)N-3′]·d[3′-(C)N-5′] as a function of the number N of base pairs for the 55th fiber model structure and the 4th fiber model structure, as indicated. Solid line with closed circles: the DNA oligomer in the neutral state in water. Dashed line with closed diamonds: the one in the ionic state in water. Dotted line with closed triangles: the one in the gas phase. Dot−dashed line with closed squares: the one without a backbone in the gas phase.