Influence of the B-site ordering on the magnetic properties of the new La3Co2MO9 double perovskites with M=Nb or Ta

Synthesis and electrical property study of La3Ni2MO9 (M=Nb and TA)

“…Perovskite structures with the general formula, ABO 3 , have been widely studied for a range of applications due to their mixed conducting properties [1][2][3][4][5][6][7][8][9]. If two atoms, B and B′, are placed on the two different crystallographic B-sites, a layered perovskite is formed.…”

“…If two atoms, B and B′, are placed on the two different crystallographic B-sites, a layered perovskite is formed. Commonly, this is referred to as the double perovskite structure, A 2 BB′O 6 , but further variation in the B and B′ ratio from 1:1 to 2:1, leads to a double perovskite with the general formula, A 3 B 2 B′O 9 [1]. Such B-site ordered perovskites have structures that are similar to the relatively open structural framework of the Ruddlesden-Popper structure which has recently been attractive for use as an electrode in intermediate temperature solid oxide fuel cell (IT-SOFCs) devices [2].…”

Synthesis and structural and magnetic characterization of the frustrated magnetic system La2Ni4/3−Co Sb2/3O6

“…Besides, the different sizes of A and B cations can lead to important structural distortions. It has been shown in some systems that the degree of order and distortions strongly affect the physical properties [9][10][11].…”

Synthesis, structure and magnetic properties of La3Co2SbO9: A double perovskite with competing antiferromagnetic and ferromagnetic interactions

“…For example, antisite disorder has been shown to be responsible for spin-glass behavior for different double perovskites, i.e., Sr 2 FeTeO 6 [13], Sr 2 Mn 0.7 Fe 0.3 O 6 [14], Sr 2 FeMoO 6 [15] among others. The double perovskites La 3 Co 2 NbO 9 and La 3 Co 2 TaO 9 were prepared by our group [16,17] by sol-gel and solid state methods and the correlation between the B order-disorder and magnetic behavior was reported. Samples prepared by solid state showed spontaneous magnetization bellow 72 K for La 3 Co 2 TaO 9 and 62 K for La 3 Co 2 NbO 9 and positive y values, showing prevalence of ferromagnetic interactions, while those prepared by sol-gel present low spontaneous magnetization (below 40 and 20 K, respectively) and negative y values, showing prevalence of antiferromagnetic interactions.…”

“…Samples prepared by solid state showed spontaneous magnetization bellow 72 K for La 3 Co 2 TaO 9 and 62 K for La 3 Co 2 NbO 9 and positive y values, showing prevalence of ferromagnetic interactions, while those prepared by sol-gel present low spontaneous magnetization (below 40 and 20 K, respectively) and negative y values, showing prevalence of antiferromagnetic interactions. This behavior was explained by a simple model which shows that the most B-site ordered compounds favors the ferromagnetic Co 2 þ -O-M 5 þ -O-Co 2 þ interactions while the most disordered ones favor the antiferromagnetic Co 2 þ -O-Co 2 þ interactions [16]. These Co 2 þ -O-M 5 þ -O-Co 2 þ ferromagnetic interactions, according to this model, are present in nanoclusters, whose amount and size are highly dependent on the degree of disorder on the B sites.…”