Temperature study of MnAs local structure by EXAFS

Extended X-ray absorption fine structure measurements at the Mn K absorption edge on MnAs in the temperature range between 10 and 300 K are reported. In accordance with previous diffraction studies, a contraction of the unit cell has been found when lowering the temperature. The Debye–Waller factors of the Mn–Mn and Mn–As first sub-shells have been fitted with a correlated Debye model plus a temperature independent static disorder, obtaining a Debye temperature around 310 K. The fit provides information about the static contribution to the local disorder along the apical Mn–Mn and along the Mn–As interatomic distances. In particular the results on the Mn–As sub-shell show strict similarities with the manganese-oxide perovskites.