Accurate determination of the exchange constant in Sr2CuO3 from recent theoretical results

Data from susceptibility measurements [Ami et al., Phys. Rev. B 51, 5994 (1995)] on Sr2CuO3 are compared with recent theoretical predictions [Eggert et al., Phys. Rev. Lett. 73, 332 (1994)] for the magnetic susceptibility of the antiferromagnetic spin-1/2 Heisenberg chain. The experimental data fully confirms the theoretical predictions and in turn we establish that Sr2CuO3 behaves almost perfectly like a one-dimensional antiferromagnet with an exchange coupling of J=1700(-100)(+150)K.