Materials Data on Ba2LaTlCu2O7 by Materials Project

Ba2LaCu2TlO7 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.66–2.99 Å. La3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are six shorter (2.53 Å) and two longer (2.54 Å) La–O bond lengths. Cu2+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.99–2.50 Å. Tl3+ is bonded in a see-saw-like geometry to four O2- atoms. There are two shorter (2.15 Å) and two longer (2.34 Å) Tl–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent La3+, and two equivalent Cu2+ atoms. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent La3+, and two equivalent Cu2+ atoms. In the third O2- site, O2- is bonded to four equivalent Ba2+, one Cu2+, and one Tl3+ atom to form a mixture of distorted corner and edge-sharing OBa4TlCu octahedra. The corner-sharing octahedra tilt angles range from 17–20°. In the fourth O2- site, O2- is bonded in a see-saw-like geometry to two equivalent Ba2+ and two equivalent Tl3+ atoms.

Ba₂LaCu₂TlO₇晶体结晶于正交晶系Pmm2空间群，其结构为三维骨架。Ba²⁺以9配位构型与9个O²⁻离子成键，Ba-O键长分布范围为2.66~2.99 Å。La³⁺以体心立方配位构型与8个O²⁻离子成键，其中包含6条键长为2.53 Å的较短La-O键，以及2条键长为2.54 Å的较长La-O键。Cu²⁺与5个O²⁻离子结合，形成共顶点CuO₅四方锥结构，Cu-O键长分布范围为1.99~2.50 Å。Tl³⁺以跷跷板型配位构型与4个O²⁻离子成键，包含2条键长为2.15 Å的较短Tl-O键，以及2条键长为2.34 Å的较长Tl-O键。该晶体存在4个不等价的O²⁻位点：在第一个O²⁻位点中，O²⁻以6配位构型分别与2个等价的Ba²⁺、2个等价的La³⁺及2个等价的Cu²⁺成键；在第二个O²⁻位点中，O²⁻以6配位构型分别与2个等价的Ba²⁺、2个等价的La³⁺及2个等价的Cu²⁺成键；在第三个O²⁻位点中，O²⁻与4个等价的Ba²⁺、1个Cu²⁺及1个Tl³⁺结合，形成兼具畸变共顶点与共边连接的OBa₄TlCu八面体结构，共顶点八面体的倾斜角范围为17°~20°；在第四个O²⁻位点中，O²⁻以跷跷板型配位构型分别与2个等价的Ba²⁺及2个等价的Tl³⁺成键。