To do so, the internal field units are converted using the nuclear g factor of 61 Ni (-0.5), the nuclear magneton (7.62 MHz/T) and making the limiting assumption that 〈𝑆〉, the expectation value of electronic spin, is 1 as defined by Equation 𝐴 𝑒𝑥𝑝 = -𝐵 𝑓𝑖𝑡 𝑔 𝑁 𝜇 𝑁 /〈𝑆〉. This results in a hyperfine coupling constant Aexp = 20.6 ± 1.1 MHz which gives an upper bound estimate for comparison to DFT calculations.