Vacancy Ordering as the Cause for the Electrical Resistivity Anomalies and Superlattice Modulations inACu7−S4(A=Tl, K, Rb)

Synthesis and characterization of KCu3S2 microstructures through a composite-hydroxide mediated method

“…Hwu and coworkers proposed a one-dimensional diffusive ordering model that indicates that the phase transition is caused by vacancy ordering involving Cu + ion diffusion along the Cu(2)-Cu(2) zigzag chains. They validated this explanation through electron diffraction measurements [12][13][14]. However, some researchers have noticed that, although the structure of KCu 3 S 2 not only possesses the building blocks found in KCu 7 S 4 , it also possesses the layered structure of K 3 Cu 8 S 6 .…”

Thiocuprates—Interesting anisotropic solids

“…K 3 Cu 8 S 6 [68], Rb 3 Cu 8 S 6 [69], TlCu 3 S 2 [64], the MCu 7−x S 4 phases [24,70], and ␣-BaCu 4 S 3 [71] exhibit low temperature phase transitions which were detected originally by anomalies in the electric and magnetic properties. Because of the low-dimensional metallic character of these compounds their properties attracted much attention.…”

Modulated Crystal Structure and Electronic Properties of Semiconductor Cu47Si91P144

“…If there are enough electrons, the Fermi level may be above the mobility edge and electrons at the Fermi level are then in localized states, and cannot conduct current through the solid [19]. It has been suggested that the Anderson mechanism is mainly responsible for metal-insulator transitions in some oxides, such as La 1±x Sr x CoO 3 and La 1±x Sr x VO 3 [20], and for anomalies in resistivity of KCu 7.68 S 4 [21]. The KCu 7.68 S 4 sulfide is a semiconductor above 200 K and a normal metallic conductor at lower temperatures.…”