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