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Colloidal AgBiS2 nanocrystals (NCs) have attracted increasing attention as a near–infrared absorbent materials with non–toxic elements and a high absorption coefficient. In recent years, colloidal AgBiS2 NCs have typically been synthesized via the hot injection method using hexamethyldisilathiane (TMS) as the sulfur source. However, the cost of TMS is one of the biggest obstacles to large–scale synthesis of colloidal AgBiS2 NCs. Herein, we synthesized colloidal AgBiS2 NCs using oleylamine@sulfur (OLA–S) solution as the sulfur source instead of TMS and optimized the synthesis conditions of colloidal AgBiS2 NCs. By controlling the reaction injection temperature and the dosage of OLA–S, colloidal AgBiS2 NCs with adjustable size can be synthesized. Compared with TMS–based colloidal AgBiS2 NCs, the colloidal AgBiS2 NCs based on OLA–S has good crystallinity and fewer defects. [ABSTRACT FROM AUTHOR]

Abstract: Ab initio calculations show an antiferromagnetic–ferromagnetic phase transition around 9–10GPa and a magnetic anomaly at 12GPa in BiFeO3. The magnetic phase transition also involves a structural and insulator–metal transition. The G-type AFM configuration under pressure leads to an increase of the y component and a decrease of the z component of the magnetization, which is caused by the splitting of the orbital from doubly degenerate e g states. Our results agree with the recent experimental results. [ABSTRACT FROM AUTHOR]

Abstract: First-principles calculations within local spin density approximation (LSDA)+U show that Bi2FeNiO6, as a potential multiferroic, possess ferrimagnetization as large as per formula unit with a relatively higher magnetic ordering temperature and a spontaneous polarization of caused mainly by the ferroelectric distortions of stereochemically active lone pair of Bi-6s2. In view of the orbital-resolved density of states (ODOS) of the Fe-3d and Ni-3d states, Fe and Ni experience charge disproportionation, as , in Bi2FeNiO6 in the rhombohedral phase. [Copyright &y& Elsevier]