LaCrAsO is Parent of FeAs superconductors structured and crystallizes in the triclinic P1 space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 4-coordinate geometry to two equivalent As(3), two equivalent As(4), one O(3), one O(4), and two equivalent O(1) atoms. In the second La site, La(2) is bonded in a 4-coordinate geometry to two equivalent As(3), two equivalent As(4), one O(3), one O(4), and two equivalent O(2) atoms. In the third La site, La(3) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), and two equivalent O(4) atoms. In the fourth La site, La(4) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), and two equivalent O(3) atoms. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one As(3), one As(4), and two equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. In the second Cr site, Cr(2) is bonded to one As(1), one As(2), and two equivalent As(3) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. In the third Cr site, Cr(3) is bonded to one As(3), one As(4), and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. In the fourth Cr site, Cr(4) is bonded to one As(1), one As(2), and two equivalent As(4) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to two equivalent La(3), two equivalent La(4), one Cr(2), one Cr(4), and two equivalent Cr(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent La(3), two equivalent La(4), one Cr(2), one Cr(4), and two equivalent Cr(3) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to two equivalent La(1), two equivalent La(2), one Cr(1), one Cr(3), and two equivalent Cr(2) atoms. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to two equivalent La(1), two equivalent La(2), one Cr(1), one Cr(3), and two equivalent Cr(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to one La(3), one La(4), and two equivalent La(1) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the second O site, O(2) is bonded to one La(3), one La(4), and two equivalent La(2) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the third O site, O(3) is bonded to one La(1), one La(2), and two equivalent La(4) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the fourth O site, O(4) is bonded to one La(1), one La(2), and two equivalent La(3) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra.
LaCrAsO is Parent of FeAs superconductors structured and crystallizes in the triclinic P1 space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 4-coordinate geometry to two equivalent As(3), two equivalent As(4), one O(3), one O(4), and two equivalent O(1) atoms. Both La(1)-As(3) bond lengths are 3.43 Å. There is one shorter (3.47 Å) and one longer (3.48 Å) La(1)-As(4) bond length. The La(1)-O(3) bond length is 2.38 Å. The La(1)-O(4) bond length is 2.38 Å. Both La(1)-O(1) bond lengths are 2.40 Å. In the second La site, La(2) is bonded in a 4-coordinate geometry to two equivalent As(3), two equivalent As(4), one O(3), one O(4), and two equivalent O(2) atoms. Both La(2)-As(3) bond lengths are 3.48 Å. Both La(2)-As(4) bond lengths are 3.44 Å. The La(2)-O(3) bond length is 2.38 Å. The La(2)-O(4) bond length is 2.38 Å. Both La(2)-O(2) bond lengths are 2.40 Å. In the third La site, La(3) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), and two equivalent O(4) atoms. Both La(3)-As(1) bond lengths are 3.44 Å. Both La(3)-As(2) bond lengths are 3.47 Å. The La(3)-O(1) bond length is 2.38 Å. The La(3)-O(2) bond length is 2.38 Å. Both La(3)-O(4) bond lengths are 2.40 Å. In the fourth La site, La(4) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), and two equivalent O(3) atoms. Both La(4)-As(1) bond lengths are 3.47 Å. Both La(4)-As(2) bond lengths are 3.44 Å. The La(4)-O(1) bond length is 2.38 Å. The La(4)-O(2) bond length is 2.38 Å. Both La(4)-O(3) bond lengths are 2.40 Å. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one As(3), one As(4), and two equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. The Cr(1)-As(3) bond length is 2.58 Å. The Cr(1)-As(4) bond length is 2.73 Å. There is one shorter (2.59 Å) and one longer (2.60 Å) Cr(1)-As(1) bond length. In the second Cr site, Cr(2) is bonded to one As(1), one As(2), and two equivalent As(3) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. The Cr(2)-As(1) bond length is 2.59 Å. The Cr(2)-As(2) bond length is 2.75 Å. There is one shorter (2.59 Å) and one longer (2.60 Å) Cr(2)-As(3) bond length. In the third Cr site, Cr(3) is bonded to one As(3), one As(4), and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. The Cr(3)-As(3) bond length is 2.75 Å. The Cr(3)-As(4) bond length is 2.59 Å. Both Cr(3)-As(2) bond lengths are 2.60 Å. In the fourth Cr site, Cr(4) is bonded to one As(1), one As(2), and two equivalent As(4) atoms to form a mixture of distorted corner and edge-sharing CrAs4 tetrahedra. The Cr(4)-As(1) bond length is 2.73 Å. The Cr(4)-As(2) bond length is 2.58 Å. There is one shorter (2.59 Å) and one longer (2.60 Å) Cr(4)-As(4) bond length. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to two equivalent La(3), two equivalent La(4), one Cr(2), one Cr(4), and two equivalent Cr(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent La(3), two equivalent La(4), one Cr(2), one Cr(4), and two equivalent Cr(3) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to two equivalent La(1), two equivalent La(2), one Cr(1), one Cr(3), and two equivalent Cr(2) atoms. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to two equivalent La(1), two equivalent La(2), one Cr(1), one Cr(3), and two equivalent Cr(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to one La(3), one La(4), and two equivalent La(1) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the second O site, O(2) is bonded to one La(3), one La(4), and two equivalent La(2) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the third O site, O(3) is bonded to one La(1), one La(2), and two equivalent La(4) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the fourth O site, O(4) is bonded to one La(1), one La(2), and two equivalent La(3) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra.