  Heusler compounds have been intensively studied owing to the important
technological advancements that they provide in the field of shape memory,
thermomagnetic energy conversion and spintronics. Many of their intriguing
properties are ultimately governed by their magnetic states and understanding
and possibly tuning them is evidently of utmost importance. In this work we
examine the \alloys alloys with Density Functional Theory simulations and
$^{55}$Mn Nuclear Magnetic Resonance and combine these two methods to carefully
describe their ground state magnetic order. In addition, we compare the results
obtained with the conventional generalized gradient approximation with the ones
of strongly constrained and appropriately normed (SCAN) semilocal functionals
for exchange and correlation. Experimental results eventually allow to
discriminate between two different scenarios identified by ab initio
simulations.
