Discovery of a Superconductor Bi(5)O(4)S(3)Cl Containing the Unique BiS(3) Layer

The BiS(2)‐based layered superconductors with structures similar to those of cuprates and iron‐based superconductors have stimulated much research interest. Here, a new quaternary compound is reported, Bi(5)O(4)S(3)Cl, which crystalizes in a tetragonal structure with P4/mmm (No. 123) space group having alternately stacking unique BiS(3) layers and Bi(2)O(2) layers along the c‐axis with a Cl atom located at the center of the unit cell. A superconducting transition above 3 K is observed for both electrical transport and magnetic measurements. Hall resistivity measurements show its multiband character with a conduction dominated by electron‐like charge carriers. The first‐principles calculations exhibit that the semiconducting parent phase Bi(5)O(4)S(3)Cl becomes metallic when sulfur vacancies are introduced, which hints the origin of superconductivity in Bi(5)O(4)S(3)Cl. The findings will inspire the exploration of new BiS‐based superconductors.