Table 3.2. Effect of local conformational coupling on the lowest-frequency normal twisting mode of a 100 bp slightly perturbed, ideal DNA homopolymer^*.

Coupled variables	${\nu }_1^0$† (cm-1)	${\nu }_1^{\mathrm{eq}}$† (cm-1)	ΔC§ (%)
	0.186	0.186
Tilt-Roll	0.186	0.186	0.0
Tilt-Twist	0.186	0.186	-0.5
Tilt-Shift	0.186	0.186	0.0
Tilt-Slide	0.186	0.186	0.0
Tilt-Rise	0.186	0.186	0.0
Roll-Twist	0.199	0.200	15.5
Roll-Shift	0.186	0.186	0.0
Roll-Slide	0.186	0.186	0.0
Roll-Rise	0.186	0.186	0.1
Twist-Shift	0.186	0.186	0.3
Twist-Slide	0.185	0.187	0.8
Twist-Rise	0.182	0.193	7.9
Shift-Slide	0.186	0.186	0.0
Shift-Rise	0.186	0.186	0.0
Slide-Rise	0.186	0.186	0.0
Roll-Twist,Twist-Rise	0.194	0.217	35.5
Twist-Slide,Twist-Rise	0.181	0.202	17.8
Roll-Twist,Twist-Slide	0.200	0.206	22.4
Roll-Twist,Twist-Slide,Twist-Rise	0.187	0.225	46.5

^*Dimeric rest state: $({\theta }_1^0,{\theta }_2^0,{\theta }_3^0,{\theta }_4^0,{\theta }_5^0,{\theta }_6^0)=(0°,5°,36°,0\mathrm{Å},0\mathrm{Å},3.4\mathrm{Å})$.

^†Frequencies of DNA chains subject to the same global constraints as in Table 3.1.

^§Change in torsional modulus of the restrained duplex subject to given conformational coupling compared to that (C = 2.03 × 10^-19 erg-cm) of the unrestrained molecule with independent fluctuations of base-pair step parameters. See legend to Table 3.1.