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Materials Data on Cr(PO3)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Cr(PO3)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Co(PO3)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Cr(PO3)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Mn(PO3)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Materials Data on Sn(PO3)2 by Materials Project

SnOP2O5 crystallizes in the orthorhombic C222_1 space group. The structure is three-dimensional. Sn2+ is bonded to four O2- atoms to form SnO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.29–2.40 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SnO4 tetrahedra and corners with two PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SnO4 tetrahedra and corners with two equivalent PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.61 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SnO4 tetrahedra and corners with two equivalent PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.63 Å) P–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sn2+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Sn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sn2+ and one P5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Sn(PO3)2 by Materials Project

SnOP2O5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Sn2+ is bonded to four O2- atoms to form SnO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.26–2.47 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SnO4 tetrahedra and corners with two equivalent PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SnO4 tetrahedra and corners with two equivalent PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.63 Å) P–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Sn2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Sn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sn2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Sn(PO3)2 by Materials Project

SnOP2O5 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.26 Å) and two longer (2.64 Å) Sn–O bond lengths. In the second Sn2+ site, Sn2+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.42–2.50 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent SnO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 17–55°. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one SnO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Sn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Sn2+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Sn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sn2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Sn(PO3)2 by Materials Project

SnOP2O5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sn–O bond distances ranging from 2.38–2.77 Å. In the second Sn2+ site, Sn2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sn–O bond distances ranging from 2.40–2.84 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.51 Å) and two longer (1.60 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two Sn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Sn2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Sn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two Sn2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Sn2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Sn2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Sn2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to two Sn2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Cd(PO5)2 by Materials Project

Cd(PO3)2(O2)2 crystallizes in the trigonal P-3 space group. The structure is three-dimensional and consists of six hydrogen peroxide molecules and one Cd(PO3)2 framework. In the Cd(PO3)2 framework, Cd is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.21 Å) and two longer (2.23 Å) Cd–O bond lengths. P is bonded to four O atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. There are three inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two equivalent P atoms. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Cd and one P atom. In the third O site, O is bonded in a 2-coordinate geometry to one Cd and one P atom.

36 MATERIALS SCIENCE↗

Materials Data on Zn(PO5)2 by Materials Project

Zn(PO3)2(O2)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four hydrogen peroxide molecules and one Zn(PO3)2 sheet oriented in the (1, 0, 0) direction. In the Zn(PO3)2 sheet, Zn is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.00 Å) and two longer (2.03 Å) Zn–O bond lengths. P is bonded in a trigonal planar geometry to three O atoms. There are a spread of P–O bond distances ranging from 1.47–1.51 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one P atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Zn and one P atom. In the third O site, O is bonded in a bent 150 degrees geometry to one Zn and one P atom.

36 MATERIALS SCIENCE↗

Materials Data on BaP2(HO3)2 by Materials Project

Ba(PO3)2H2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional and consists of twelve hydrogen molecules and one Ba(PO3)2 framework. In the Ba(PO3)2 framework, there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.67–2.93 Å. In the second Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.58–3.08 Å. In the third Ba2+ site, Ba2+ is bonded in a 2-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.64–3.20 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.66 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.64 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Ba2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ba2+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Ba2+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a single-bond geometry to two Ba2+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ba2+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on ThP2H2CO8 by Materials Project

Th(PO3)2CH2O2 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional and consists of four hydrogen peroxide;methane molecules and one Th(PO3)2 framework. In the Th(PO3)2 framework, Th4+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Th–O bond distances ranging from 2.28–2.37 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. All P–O bond lengths are 1.54 Å. In the second P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one P5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ag3P6H12N3O19 by Materials Project

(Ag(PO3)2)6(NH4)6O2 crystallizes in the trigonal R-3 space group. The structure is three-dimensional and consists of eighteen ammonium molecules, six water molecules, and one Ag(PO3)2 framework. In the Ag(PO3)2 framework, Ag+1.67+ is bonded to five O2- atoms to form distorted AgO5 trigonal bipyramids that share corners with five PO4 tetrahedra and an edgeedge with one AgO5 trigonal bipyramid. There are a spread of Ag–O bond distances ranging from 2.37–2.65 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent PO4 tetrahedra and corners with two equivalent AgO5 trigonal bipyramids. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent PO4 tetrahedra and corners with three equivalent AgO5 trigonal bipyramids. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent P5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ag+1.67+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ag+1.67+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent P5+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Ag+1.67+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Ag+1.67+ and one P5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Mo(PO4)2 by Materials Project

MoO2(PO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Mo6+ sites. In the first Mo6+ site, Mo6+ is bonded to six O2- atoms to form distorted MoO6 octahedra that share corners with five PO4 tetrahedra. There are a spread of Mo–O bond distances ranging from 1.69–2.22 Å. In the second Mo6+ site, Mo6+ is bonded to six O2- atoms to form distorted MoO6 octahedra that share corners with five PO4 tetrahedra. There are a spread of Mo–O bond distances ranging from 1.69–2.30 Å. In the third Mo6+ site, Mo6+ is bonded to six O2- atoms to form distorted MoO6 octahedra that share corners with five PO4 tetrahedra. There are a spread of Mo–O bond distances ranging from 1.70–2.23 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent MoO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 20–36°. There are a spread of P–O bond distances ranging from 1.46–1.65 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MoO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 12–45°. There are a spread of P–O bond distances ranging from 1.50–1.60 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MoO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 6–45°. There are a spread of P–O bond distances ranging from 1.49–1.60 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two MoO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 22–37°. There are a spread of P–O bond distances ranging from 1.46–1.65 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three MoO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are a spread of P–O bond distances ranging from 1.49–1.60 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two MoO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–36°. There are a spread of P–O bond distances ranging from 1.46–1.64 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one Mo6+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the fourteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a linear geometry to one Mo6+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the twentieth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mo6+ and one P5+ atom. In the twenty-first O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the twenty-second O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom. In the twenty-third O2- site, O2- is bonded in a distorted linear geometry to one Mo6+ and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Mo6+ and one P5+ atom.

36 MATERIALS SCIENCE↗

Catalysis of hydrolysis and nucleophilic substitution at the P-N bond of phosphoimidazolide-activated nucleotides in phosphate buffers

Phosphoimidazolide-activated derivatives of guanosine and cytidine 5'-monophosphates, henceforth called ImpN's, exhibit enhanced rates of degradation in the presence of aqueous inorganic phosphate in the range 4.0 < or = pH < or = 8.6. This degradation is been attributed to (i) nucleophilic substitution of the imidazolide and (ii) catalysis of the P-N bond hydrolysis by phosphate. The first reaction results in the formation of nucleoside 5'-diphosphate and the second in nucleoside 5'-monophosphate. Analysis of the observed rates as well as the product ratios as a function of pH and phosphate concentration allow distinction between various mechanistic possibilities. The results show that both H2PO4- and HPO4(2-) participate in both hydrolysis and nucleophilic substitution. Statistically corrected biomolecular rate constants indicate that the dianion is 4 times more effective as a general base than the monoanion, and 8 times more effective as nucleophile. The low Bronsted value beta = 0.15 calculated for these phosphate species, presumed to act as general bases in facilitating water attack, is consistent with the fact that catalysis of the hydrolysis of the P-N bond in ImpN's has not been detected before. The beta nuc = 0.35 calculated for water, H2PO4-, HPO4(2-), and hydroxide acting as nucleophiles indicates a more associative transition state for nucleotidyl (O2POR- with R = nucleoside) transfers than that observed for phosphoryl (PO3(2-)) transfers (beta nuc = 0.25). With respect to the stability/reactivity of ImpN's under prebiotic conditions, our study shows that these materials would not suffer additional degradation due to inorganic phosphate, assuming the concentrations of phosphate, Pi, on prebiotic Earth were similar to those in the present oceans ([Pi] approximately 2.25 micromoles).

NASA Discipline Number 52-20↗

Materials Data on VP2O7 by Materials Project

VO(PO3)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. V4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of V–O bond distances ranging from 1.63–2.01 Å. P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.61 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one V4+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to one V4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent P5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on P2PbO6 by Materials Project

Pb(PO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Pb–O bond distances ranging from 2.48–2.91 Å. In the second Pb2+ site, Pb2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pb–O bond distances ranging from 2.47–3.06 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Pb2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Pb2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to two Pb2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom.

36 MATERIALS SCIENCE↗