Several new hydrides from the series R2Ni2InHx (R = La, Ce, Pr, Nd; x 4.5 - 5.0) were synthesized. They are based on initial compounds of the R2Ni2In type crystallizing in the Mo2FeB2-structure.
So as to accommodate high amount of H atoms (x can theoretically reach the value of 6), the structure changes to orthorhombic, space group Pbam, while the unit-cell volume increases by 10-20 %. Nd2Ni2In was found antiferromagnetic, with a first order magnetic phase transition at TN = 8 K.
Applied magnetic field moH { 0.3 T induces ferromagnetism. TN of Nd2Ni2InH4.5, which is a more regular antiferromagnet, is reduced to 5 K.