Value for equlibrium constant question! Please help with homework!! Due today

What is the value of the equilibrium constant for transformation of carbon from graphite to diamond at 360.0 C?
Substance ΔfH0
kJ/mol S0
J/mol K
graphite 0.0 5.7
diamond 1.9 2.4

So the reaction is C(graphite) --> C(diamond)

For this reaction ΔH = ΔHf(diamond) - ΔHf(graphite) = 1.9 kJ/mol

ΔS = So(diamond) - So(graphite) = 2.4 J/molK - 5.7 J/mol K = - 3.3 J/mol K

ΔG = ΔH - TΔS = 1900 J/mol - 633 K (-3.3 J/molK) = 3989 J/mol

Now ΔG = -RT ln K
3989 J/mol = - 8.314 J/molK (633K) ln K
ln K = -0.758
K = 0.47