title: Sr14Sn3As12 and Eu14Sn3As12: enantiomorph-like Zintl compounds.
abstract: Two new chiral Zintl compounds, Sr14Sn3As12 and Eu14Sn3As12, were synthesized from tin-flux reactions, and the structures were determined by using single-crystal X-ray diffraction. Both compounds crystallize in the trigonal space group R3 (No. 146, Z = 3) with the anion structures containing various units: dumbbell-shaped [Sn2As6](12-) dimers, [SnAs3](7-) triangular pyramids, and isolated As(3-) anions. Very interestingly, these two compounds exhibit opposite chirality in the observed crystal structures, resembling enantiomorphs. Detailed structure analyses suggest possible steric effects among the anion clusters, and on the basis of the calculated electronic structures, substantial electron lone pairs exist on the anions of both compounds, which may provide a hint to understanding the origination of chirality in these intermetallic compounds.
authors.affiliation: State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University , Jinan, Shandong 250100, Peoples Republic of China.
authors.forename: Xiao-Cun
authors.initials: XC
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University , Jinan, Shandong 250100, Peoples Republic of China.
authors.forename: Ming-Yan
authors.initials: MY
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University , Jinan, Shandong 250100, Peoples Republic of China.
authors.forename: Sheng-Qing
authors.initials: SQ
authors.lastname: Xia
authors.affiliation: State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University , Jinan, Shandong 250100, Peoples Republic of China.
authors.forename: Xu-Tang
authors.initials: XT
authors.lastname: Tao