With the μ2 criteria selected, we are now ready to define the procedure used to select the k3 AB coefficient for each atomic pair (with 94 elements considered, this results in 4465 distinct pairs). We start by selecting pair AB and computing C6 AB (CN A ,CN B ) with k3=4, investigating the case when CN A =CN B . With this function at hand, we compute the first derivatives to determine the peak positions and then compute the second derivatives (i.e., the μ2 criteria). If any of the peaks exhibit μ2>400, we consider that k3 is too large for this pair and decrease the value until no sharp peaks remain. The number 400 was chosen as a balance between maintaining accuracy and preventing the presence of artifacts with larger k3 values. The new k3 AB value can then be found for each unique atomic pair combination.