ZrNb4CN4 is alpha Po-derived structured and crystallizes in the trigonal R3m space group. Zr(1) is bonded to three equivalent C(1) and three equivalent N(4) atoms to form ZrC3N3 octahedra that share corners with three equivalent Nb(1)C3N3 octahedra, corners with three equivalent Nb(4)N6 octahedra, edges with three equivalent Nb(1)C3N3 octahedra, edges with three equivalent Nb(4)N6 octahedra, and edges with six equivalent Zr(1)C3N3 octahedra. The corner-sharing octahedral tilt angles are 3°. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to three equivalent C(1) and three equivalent N(1) atoms to form NbC3N3 octahedra that share corners with three equivalent Zr(1)C3N3 octahedra, corners with three equivalent Nb(2)N6 octahedra, edges with three equivalent Zr(1)C3N3 octahedra, edges with three equivalent Nb(2)N6 octahedra, and edges with six equivalent Nb(1)C3N3 octahedra. The corner-sharing octahedral tilt angles are 3°. In the second Nb site, Nb(2) is bonded to three equivalent N(1) and three equivalent N(2) atoms to form NbN6 octahedra that share corners with three equivalent Nb(1)C3N3 octahedra, corners with three equivalent Nb(3)N6 octahedra, edges with three equivalent Nb(1)C3N3 octahedra, edges with three equivalent Nb(3)N6 octahedra, and edges with six equivalent Nb(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the third Nb site, Nb(3) is bonded to three equivalent N(2) and three equivalent N(3) atoms to form a mixture of edge and corner-sharing NbN6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth Nb site, Nb(4) is bonded to three equivalent N(3) and three equivalent N(4) atoms to form NbN6 octahedra that share corners with three equivalent Zr(1)C3N3 octahedra, corners with three equivalent Nb(3)N6 octahedra, edges with three equivalent Zr(1)C3N3 octahedra, edges with three equivalent Nb(3)N6 octahedra, and edges with six equivalent Nb(4)N6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. C(1) is bonded to three equivalent Zr(1) and three equivalent Nb(1) atoms to form CZr3Nb3 octahedra that share corners with three equivalent N(1)Nb6 octahedra, corners with three equivalent N(4)Zr3Nb3 octahedra, edges with three equivalent N(1)Nb6 octahedra, edges with three equivalent N(4)Zr3Nb3 octahedra, and edges with six equivalent C(1)Zr3Nb3 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. There are four inequivalent N sites. In the first N site, N(1) is bonded to three equivalent Nb(1) and three equivalent Nb(2) atoms to form NNb6 octahedra that share corners with three equivalent C(1)Zr3Nb3 octahedra, corners with three equivalent N(2)Nb6 octahedra, edges with three equivalent C(1)Zr3Nb3 octahedra, edges with three equivalent N(2)Nb6 octahedra, and edges with six equivalent N(1)Nb6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the second N site, N(2) is bonded to three equivalent Nb(2) and three equivalent Nb(3) atoms to form a mixture of edge and corner-sharing NNb6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third N site, N(3) is bonded to three equivalent Nb(3) and three equivalent Nb(4) atoms to form NNb6 octahedra that share corners with three equivalent N(2)Nb6 octahedra, corners with three equivalent N(4)Zr3Nb3 octahedra, edges with three equivalent N(2)Nb6 octahedra, edges with three equivalent N(4)Zr3Nb3 octahedra, and edges with six equivalent N(3)Nb6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the fourth N site, N(4) is bonded to three equivalent Zr(1) and three equivalent Nb(4) atoms to form NZr3Nb3 octahedra that share corners with three equivalent C(1)Zr3Nb3 octahedra, corners with three equivalent N(3)Nb6 octahedra, edges with three equivalent C(1)Zr3Nb3 octahedra, edges with three equivalent N(3)Nb6 octahedra, and edges with six equivalent N(4)Zr3Nb3 octahedra. The corner-sharing octahedral tilt angles are 1°.
ZrNb4CN4 is alpha Po-derived structured and crystallizes in the trigonal R3m space group. Zr(1) is bonded to three equivalent C(1) and three equivalent N(4) atoms to form ZrC3N3 octahedra that share corners with three equivalent Nb(1)C3N3 octahedra, corners with three equivalent Nb(4)N6 octahedra, edges with three equivalent Nb(1)C3N3 octahedra, edges with three equivalent Nb(4)N6 octahedra, and edges with six equivalent Zr(1)C3N3 octahedra. The corner-sharing octahedral tilt angles are 3°. All Zr(1)-C(1) bond lengths are 2.29 Å. All Zr(1)-N(4) bond lengths are 2.33 Å. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to three equivalent C(1) and three equivalent N(1) atoms to form NbC3N3 octahedra that share corners with three equivalent Zr(1)C3N3 octahedra, corners with three equivalent Nb(2)N6 octahedra, edges with three equivalent Zr(1)C3N3 octahedra, edges with three equivalent Nb(2)N6 octahedra, and edges with six equivalent Nb(1)C3N3 octahedra. The corner-sharing octahedral tilt angles are 3°. All Nb(1)-C(1) bond lengths are 2.21 Å. All Nb(1)-N(1) bond lengths are 2.30 Å. In the second Nb site, Nb(2) is bonded to three equivalent N(1) and three equivalent N(2) atoms to form NbN6 octahedra that share corners with three equivalent Nb(1)C3N3 octahedra, corners with three equivalent Nb(3)N6 octahedra, edges with three equivalent Nb(1)C3N3 octahedra, edges with three equivalent Nb(3)N6 octahedra, and edges with six equivalent Nb(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. All Nb(2)-N(1) bond lengths are 2.22 Å. All Nb(2)-N(2) bond lengths are 2.25 Å. In the third Nb site, Nb(3) is bonded to three equivalent N(2) and three equivalent N(3) atoms to form a mixture of edge and corner-sharing NbN6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. All Nb(3)-N(2) bond lengths are 2.23 Å. All Nb(3)-N(3) bond lengths are 2.22 Å. In the fourth Nb site, Nb(4) is bonded to three equivalent N(3) and three equivalent N(4) atoms to form NbN6 octahedra that share corners with three equivalent Zr(1)C3N3 octahedra, corners with three equivalent Nb(3)N6 octahedra, edges with three equivalent Zr(1)C3N3 octahedra, edges with three equivalent Nb(3)N6 octahedra, and edges with six equivalent Nb(4)N6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. All Nb(4)-N(3) bond lengths are 2.23 Å. All Nb(4)-N(4) bond lengths are 2.24 Å. C(1) is bonded to three equivalent Zr(1) and three equivalent Nb(1) atoms to form CZr3Nb3 octahedra that share corners with three equivalent N(1)Nb6 octahedra, corners with three equivalent N(4)Zr3Nb3 octahedra, edges with three equivalent N(1)Nb6 octahedra, edges with three equivalent N(4)Zr3Nb3 octahedra, and edges with six equivalent C(1)Zr3Nb3 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. There are four inequivalent N sites. In the first N site, N(1) is bonded to three equivalent Nb(1) and three equivalent Nb(2) atoms to form NNb6 octahedra that share corners with three equivalent C(1)Zr3Nb3 octahedra, corners with three equivalent N(2)Nb6 octahedra, edges with three equivalent C(1)Zr3Nb3 octahedra, edges with three equivalent N(2)Nb6 octahedra, and edges with six equivalent N(1)Nb6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the second N site, N(2) is bonded to three equivalent Nb(2) and three equivalent Nb(3) atoms to form a mixture of edge and corner-sharing NNb6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third N site, N(3) is bonded to three equivalent Nb(3) and three equivalent Nb(4) atoms to form NNb6 octahedra that share corners with three equivalent N(2)Nb6 octahedra, corners with three equivalent N(4)Zr3Nb3 octahedra, edges with three equivalent N(2)Nb6 octahedra, edges with three equivalent N(4)Zr3Nb3 octahedra, and edges with six equivalent N(3)Nb6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the fourth N site, N(4) is bonded to three equivalent Zr(1) and three equivalent Nb(4) atoms to form NZr3Nb3 octahedra that share corners with three equivalent C(1)Zr3Nb3 octahedra, corners with three equivalent N(3)Nb6 octahedra, edges with three equivalent C(1)Zr3Nb3 octahedra, edges with three equivalent N(3)Nb6 octahedra, and edges with six equivalent N(4)Zr3Nb3 octahedra. The corner-sharing octahedral tilt angles are 1°.