Loop Free-Energy Decomposition

Dimer 1

ΔG = 0.2 kcal/mol ΔH = 1.0 kcal/mol ΔS = 2.3 e.u. T_m = -321.7°C

Structural element	δδG	Information
External loop	-1.04	17 ss bases & 1 closing helices
Stack	-0.23	External closing pair is A11-T12
Helix	-0.23	2 base pairs
External loop	+1.51	Closing pair is T12-A11

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Dimer 2

ΔG = -0.4 kcal/mol ΔH = -5.4 kcal/mol ΔS = -15.0 e.u. T_m = -130.6°C

Structural element	δδG	Information
External loop	-0.55	1 ss bases & 1 closing helices
Stack	-0.74	External closing pair is A1-T18
Stack	-0.62	External closing pair is C2-G17
Helix	-1.36	3 base pairs
External loop	+1.51	Closing pair is T3-A16

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Dimer 3

ΔG = -0.9 kcal/mol ΔH = -33.9 kcal/mol ΔS = -99.1 e.u. T_m = -1.3°C

Structural element	δδG	Information
External loop	-0.64	23 ss bases & 1 closing helices
Stack	-0.74	External closing pair is A14-T9
Stack	-0.75	External closing pair is C15-G8
Stack	-0.62	External closing pair is A16-T7
Helix	-2.11	4 base pairs
External loop	+1.85	Closing pair is G17-C6