Coexistence of spin ordering on ladders and spin dimer formation in a new-structure-type compound Sr2Co3S2O3

Abstract

We report on the syntheses and characterizations of single crystalline and polycrystalline Sr2Co3S2O3 with a novel crystal structure type. It contains Co–O 2-leg rectangular ladders and necklace ladders. The two ladders share common legs and construct a hybrid spin ladder. A rare meridional heteroleptic octahedral coordination is found for the Co2+ ions in the 2-leg ladder. Within the necklace ladders, the Co2+ ions are in trans-octahedral coordination. An antiferromagnetic order is observed at TN ~ 267 K, while a broad maximum in magnetic susceptibility is found below TN. This relatively high ordering temperature among Co-based ladder compounds is related to the highly anisotropic mer-coordination of the Co2+ ions. The trans-octahedrally coordinated Co2+ ions, on the other hand, corresponds to the possible short-range magnetic correlations through dimers with an effective . This results in a rare situation that spin ordering and spin dimers coexist down to 2 K.

Easing the Monte Carlo sign problem

“…Frustration gives rise to a plethora of phenomena arising in quasi-one-dimensional systems such as the emergence of quantum spin liquids (37,38) and the interplay of spin-1/2 and spin-1 physics (39). They are also somewhat more realistic descriptions of actual low-dimensional experimental situations than simple one-dimensional chains, serving as a model for small couplings in the transverse direction (35,40,41). Therefore, quasi-one-dimensional systems are often seen as a stepping stone toward studying higher dimensions (42), where the sign problem inhibits QMC simulations (43), and thus serve as the perfect playground for a proof of principle.…”

A semi-empirical analysis of the paramagnetic susceptibility of solid state magnetic clusters

“…The fitting and experimental data are presented in Figure 1 Lastly, as discussed in Ref. [17], the Sr 3 Co 3 S 2 O 3 compound was expected to hold an effective spin S = 3/2 because of the Co 2+ valence, which is again deduced from charge balance. Due to the octahedral crystal field, however, Co 2+ cations carry low S = 1/2 spins.…”

“…We select the Ba 3 Mn 2 O 8 [14][15][16], Sr 3 Cr 2 O 8 [11], and Sr 3 Co 3 S 2 O 3 [17] spin dimer materials to our analysis. The same trigonal structure, described by the space group R 3m, are shared by the two former materials and is depicted in Figure 1(a).…”

Easing the Monte Carlo sign problem

“…Frustration gives rise to a plethora of phenomena arising in quasi one-dimensional systems such as the emergence of quantum spin liquids [36,37] and the interplay of spin-1/2 and spin-1 physics [38]. They are also somewhat more realistic descriptions of actual low-dimensional experimental situations than simple onedimensional chains, serving as a model for small couplings in the transverse direction [34,39,40]. Therefore quasi onedimensional systems are often seen as a stepping stone towards studying higher dimensions [41], where the sign problem inhibits QMC simulations for exotic states of matter [42].…”