DOE OSTI2020
CaMnAl4SiP3H5O18O2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional and consists of four hydrogen peroxide molecules and one CaMnAl4SiP3H5O18 framework. In the CaMnAl4SiP3H5O18 framework, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.41–2.63 Å. Mn2+ is bonded in a 6-coordinate geometry to two equivalent H1+ and four O2- atoms. Both Mn–H bond lengths are 1.95 Å. There are a spread of Mn–O bond distances ranging from 1.86–2.12 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent PO4 tetrahedra and an edgeedge with one AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.93 Å. In the second Al3+ site, Al3+ is bonded to two H1+ and three O2- atoms to form distorted AlH2O3 trigonal bipyramids that share corners with two equivalent SiHO3 tetrahedra and an edgeedge with one AlH2O3 trigonal bipyramid. There is one shorter (1.67 Å) and one longer (1.70 Å) Al–H bond length. There are a spread of Al–O bond distances ranging from 1.83–1.91 Å. Si4+ is bonded to one H1+ and three O2- atoms to form SiHO3 tetrahedra that share corners with four equivalent AlH2O3 trigonal bipyramids. The Si–H bond length is 1.48 Å. There is two shorter (1.65 Å) and one longer (1.66 Å) Si–O bond length. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.51 Å) and one longer (1.77 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent AlO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one Si4+ atom. In the third H1+ site, H1+ is bonded in a bent 120 degrees geometry to one Mn2+ and one Al3+ atom. In the fourth H1+ site, H1+ is bonded in a water-like geometry to two equivalent Al3+ atoms. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Al3+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a linear geometry to one Al3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Mn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Al3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Al3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ca2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one P5+ and one O2- atom. The O–O bond length is 1.51 Å. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mn2+ and two equivalent Al3+ atoms. In the tenth O2- site, O2- is bonded in a distorted water-like geometry to one Mn2+ and one H1+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one O2- atom.