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Na3Ca7Ti7Nb3O30 is (Cubic) Perovskite-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with four NaO12 cuboctahedra, corners with eight CaO12 cuboctahedra, faces with three NaO12 cuboctahedra, faces with three CaO12 cuboctahedra, faces with four TiO6 octahedra, and faces with four NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.77–2.91 Å. In the second Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with six NaO12 cuboctahedra, corners with six CaO12 cuboctahedra, a faceface with one CaO12 cuboctahedra, faces with five NaO12 cuboctahedra, faces with two equivalent TiO6 octahedra, and faces with six NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.74–2.95 Å. In the third Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with six NaO12 cuboctahedra, corners with six CaO12 cuboctahedra, faces with two CaO12 cuboctahedra, faces with four NaO12 cuboctahedra, faces with two equivalent TiO6 octahedra, and faces with six NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.73–2.87 Å. There are seven inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with two equivalent NaO12 cuboctahedra, corners with ten CaO12 cuboctahedra, a faceface with one NaO12 cuboctahedra, faces with five CaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.66–2.84 Å. In the second Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form distorted CaO12 cuboctahedra that share corners with four CaO12 cuboctahedra, corners with eight NaO12 cuboctahedra, faces with three NaO12 cuboctahedra, faces with three CaO12 cuboctahedra, faces with four TiO6 octahedra, and faces with four NbO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.55–2.95 Å. In the third Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with twelve CaO12 cuboctahedra, faces with six CaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.72–2.80 Å. In the fourth Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with twelve CaO12 cuboctahedra, faces with six CaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.72–2.80 Å. In the fifth Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four NaO12 cuboctahedra, corners with eight CaO12 cuboctahedra, a faceface with one NaO12 cuboctahedra, faces with five CaO12 cuboctahedra, faces with two equivalent NbO6 octahedra, and faces with six TiO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.63–2.87 Å. In the sixth Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with two equivalent NaO12 cuboctahedra, corners with ten CaO12 cuboctahedra, faces with six CaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.62–2.84 Å. In the seventh Ca2+ site, Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four NaO12 cuboctahedra, corners with eight CaO12 cuboctahedra, a faceface with one NaO12 cuboctahedra, faces with five CaO12 cuboctahedra, faces with two equivalent NbO6 octahedra, and faces with six TiO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.63–2.87 Å. There are seven inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with five TiO6 octahedra, faces with two equivalent NaO12 cuboctahedra, and faces with six CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are a spread of Ti–O bond distances ranging from 1.93–1.99 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with eight CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ti–O bond distances ranging from 1.92–1.98 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with five TiO6 octahedra, faces with two equivalent NaO12 cuboctahedra, and faces with six CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Ti–O bond distances ranging from 1.91–1.98 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with eight CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Ti–O bond distances ranging from 1.92–1.97 Å. In the fifth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with eight CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ti–O bond distances ranging from 1.94–1.97 Å. In the sixth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three TiO6 octahedra, corners with three NbO6 octahedra, faces with four NaO12 cuboctahedra, and faces with four CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Ti–O bond distances ranging from 1.95–1.99 Å. In the seventh Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with five TiO6 octahedra, and faces with eight CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Ti–O bond distances ranging from 1.93–1.97 Å. There are three inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two TiO6 octahedra, corners with four NbO6 octahedra, faces with two equivalent CaO12 cuboctahedra, and faces with six NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are a spread of Nb–O bond distances ranging from 1.96–2.06 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three TiO6 octahedra, corners with three NbO6 octahedra, faces with four NaO12 cuboctahedra, and faces with four CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Nb–O bond distances ranging from 1.97–2.00 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with five NbO6 octahedra, faces with two equivalent CaO12 cuboctahedra, and faces with six NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are a spread of Nb–O bond distances ranging from 1.96–2.04 Å. There are thirty inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+, three Ca2+, and two equivalent Ti4+ atoms to form distorted ONaCa3Ti2 octahedra that share corners with two equivalent ONaCa3Ti2 octahedra and faces with two equivalent OCa4Ti2 octahedra. The corner-sharing octahedral tilt angles are 7°. In the second O2- site, O2- is bonded in a distorted linear geometry to one Na1+, three Ca2+, and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two equivalent Ti4+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two equivalent Ti4+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to three Na1+, one Ca2+, and two equivalent Nb5+ atoms. In the eighth O2- site, O2- is bonded in a distorted linear geometry to two Na1+, two Ca2+, and two equivalent Nb5+ atoms. In the ninth O2- site, O2- is bonded in a distorted linear geometry to three Na1+, one Ca2+, and two equivalent Nb5+ atoms. In the tenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Ca2+, and two Ti4+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+, two equivalent Ca2+, one Ti4+, and one Nb5+ atom. In the twelfth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the fourteenth O2- site, O2- is bonded to four Ca2+ and two Ti4+ atoms to form distorted OCa4Ti2 octahedra that share edges with two equivalent OCa4Ti2 octahedra and faces with two equivalent ONaCa3Ti2 octahedra. In the fifteenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Ca2+, one Ti4+, and one Nb5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the twentieth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Ca2+, one Ti4+, and one Nb5+ atom. In the twenty-first O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the twenty-third O2- site, O2- is bonded in a distorted linear geometry to four Ca2+ and two Ti4+ atoms. In the twenty-fourth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two Nb5+ atoms. In the twenty-fifth O2- site, O2- is bonded to four Na1+, one Ti4+, and one Nb5+ atom to form distorted edge-sharing ONa4TiNb octahedra. In the twenty-sixth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Ca2+, one Ti4+, and one Nb5+ atom. In the twenty-seventh O2- site, O2- is bonded in a distorted linear geometry to four Ca2+, one Ti4+, and one Nb5+ atom. In the twenty-eighth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Ca2+, and two Nb5+ atoms. In the twenty-ninth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two Nb5+ atoms. In the thirtieth O2- site, O2- is bonded in a distorted linear geometry to two Na1+, two Ca2+, and two equivalent Ti4+ atoms.

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