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P(CH3)3PBr3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four phosphorus tribromide molecules and four trimethylphosphine molecules.
PF5 crystallizes in the hexagonal P6_3/mmc space group. The structure is zero-dimensional and consists of two phosphorus pentafluoride molecules. P5+ is bonded in a trigonal bipyramidal geometry to five F1- atoms. There is three shorter (1.56 Å) and two longer (1.61 Å) P–F bond length. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one P5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one P5+ atom.
Mg2(PO4)OH crystallizes in the monoclinic Cm space group. The structure is three-dimensional and consists of two phosphorus oxide (po) molecules and one Mg12P5H3O29 framework. In the Mg12P5H3O29 framework, there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent MgO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–71°. There are a spread of Mg–O bond distances ranging from 2.04–2.29 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent MgO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–71°. There are a spread of Mg–O bond distances ranging from 2.04–2.29 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, corners with four PO4 tetrahedra, edges with two equivalent MgO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–71°. There are a spread of Mg–O bond distances ranging from 2.04–2.29 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with three MgO6 octahedra, corners with three PO4 tetrahedra, edges with two equivalent MgO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–61°. There are a spread of Mg–O bond distances ranging from 2.03–2.40 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with three MgO6 octahedra, corners with three PO4 tetrahedra, edges with two equivalent MgO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–61°. There are a spread of Mg–O bond distances ranging from 2.03–2.40 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with three MgO6 octahedra, corners with three PO4 tetrahedra, edges with two equivalent MgO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–61°. There are a spread of Mg–O bond distances ranging from 2.03–2.40 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 nine MgO6 octahedra. The corner-sharing octahedra tilt angles range from 40–70°. There is three shorter (1.55 Å) and one longer (1.57 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 eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–61°. There is two shorter (1.55 Å) and two longer (1.56 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 eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 45–61°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. There are two 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 O2- atom. The H–O bond length is 0.98 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Mg2+ and one O2- atom. The O–O bond length is 1.55 Å. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one O2- atom. The O–O bond length is 1.55 Å. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Mg2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to two Mg2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Mg2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a tetrahedral geometry to three Mg2+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to four Mg2+ and one O2- atom. In the fourteenth O2- site, O2- is bonded in a 5-coordinate geometry to four Mg2+ and one O2- atom. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to four Mg2+ and one H1+ atom. In the sixteenth O2- site, O2- is bonded in a distorted single-bond geometry to four Mg2+ and one H1+ atom.
Cr(CO)5PCl3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four phosphorus trichloride molecules and four Cr(CO)5 clusters. In each Cr(CO)5 cluster, Cr3+ is bonded in a square pyramidal geometry to five C1+ atoms. There is one shorter (1.90 Å) and four longer (1.92 Å) Cr–C bond length. There are five inequivalent C1+ sites. In the first C1+ site, C1+ is bonded in a distorted linear geometry to one Cr3+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C1+ site, C1+ is bonded in a distorted linear geometry to one Cr3+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C1+ site, C1+ is bonded in a distorted linear geometry to one Cr3+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C1+ site, C1+ is bonded in a linear geometry to one Cr3+ and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C1+ site, C1+ is bonded in a linear geometry to one Cr3+ and one O2- atom. The C–O bond length is 1.16 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C1+ atom.
CuPO2Cu2NO3PO crystallizes in the orthorhombic Pna2_1 space group. The structure is one-dimensional and consists of four phosphorus oxide (po) molecules; four Cu2NO3 clusters; and two CuPO2 ribbons oriented in the (0, 1, 0) direction. In each Cu2NO3 cluster, there are two inequivalent Cu+1.67+ sites. In the first Cu+1.67+ site, Cu+1.67+ is bonded in a single-bond geometry to one O2- atom. The Cu–O bond length is 1.97 Å. In the second Cu+1.67+ site, Cu+1.67+ is bonded in a single-bond geometry to one O2- atom. The Cu–O bond length is 1.97 Å. N3- is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.24 Å) and two longer (1.29 Å) N–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu+1.67+ and one N3- atom. In the second O2- site, O2- is bonded in a single-bond geometry to one N3- atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu+1.67+ and one N3- atom. In each CuPO2 ribbon, Cu+1.67+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.83 Å) and one longer (1.86 Å) Cu–O bond length. P5+ is bonded in a water-like geometry to two O2- atoms. There is one shorter (1.54 Å) and one longer (1.55 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one Cu+1.67+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu+1.67+ and one P5+ atom.
PHBr3As2F11 is beta-prime cadmium gold structured and crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two phosphorus tribromide molecules and two As2F11 clusters. In each As2F11 cluster, there are two inequivalent As4+ sites. In the first As4+ site, As4+ is bonded to six F1- atoms to form corner-sharing AsF6 octahedra. The corner-sharing octahedral tilt angles are 35°. There is five shorter (1.76 Å) and one longer (1.90 Å) As–F bond length. In the second As4+ site, As4+ is bonded to six F1- atoms to form corner-sharing AsF6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are a spread of As–F bond distances ranging from 1.74–2.09 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As4+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As4+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As4+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As4+ atom. In the sixth F1- site, F1- is bonded in a bent 150 degrees geometry to two As4+ atoms. In the seventh F1- site, F1- is bonded in a single-bond geometry to one As4+ atom. In the eighth F1- site, F1- is bonded in a single-bond geometry to one As4+ atom.
(RePNOCl6)2POCl3 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four phosphorus oxychloride molecules and two RePNOCl6 clusters. In one of the RePNOCl6 clusters, there are two inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded to two N3-, one O2-, and three Cl1- atoms to form distorted ReN2Cl3O octahedra that share a cornercorner with one PCl3O tetrahedra. There is one shorter (1.72 Å) and one longer (2.04 Å) Re–N bond length. The Re–O bond length is 2.38 Å. There are one shorter (2.31 Å) and two longer (2.33 Å) Re–Cl bond lengths. In the second Re6+ site, Re6+ is bonded in a 6-coordinate geometry to two N3-, one O2-, and three Cl1- atoms. There is one shorter (1.71 Å) and one longer (2.01 Å) Re–N bond length. The Re–O bond length is 2.55 Å. There are a spread of Re–Cl bond distances ranging from 2.31–2.34 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to one O2- and three Cl1- atoms to form PCl3O tetrahedra that share a cornercorner with one ReN2Cl3O octahedra. The corner-sharing octahedral tilt angles are 27°. The P–O bond length is 1.49 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. In the second P5+ site, P5+ is bonded in a tetrahedral geometry to one O2- and three Cl1- atoms. The P–O bond length is 1.49 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. In the second N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Re6+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Re6+ and one P5+ atom. There are twelve inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the eighth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the tenth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the eleventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the twelfth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In one of the RePNOCl6 clusters, there are two inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded to two N3-, one O2-, and three Cl1- atoms to form distorted ReN2Cl3O octahedra that share corners with two equivalent ReN2Cl3O octahedra and a cornercorner with one PCl3O tetrahedra. The corner-sharing octahedra tilt angles range from 4–8°. There is one shorter (1.71 Å) and one longer (2.01 Å) Re–N bond length. The Re–O bond length is 2.42 Å. There are a spread of Re–Cl bond distances ranging from 2.32–2.34 Å. In the second Re6+ site, Re6+ is bonded to two N3-, one O2-, and three Cl1- atoms to form distorted ReN2Cl3O octahedra that share corners with two equivalent ReN2Cl3O octahedra and a cornercorner with one PCl3O tetrahedra. The corner-sharing octahedra tilt angles range from 4–8°. There is one shorter (1.71 Å) and one longer (2.02 Å) Re–N bond length. The Re–O bond length is 2.40 Å. There are one shorter (2.32 Å) and two longer (2.33 Å) Re–Cl bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to one O2- and three Cl1- atoms to form PCl3O tetrahedra that share a cornercorner with one ReN2Cl3O octahedra. The corner-sharing octahedral tilt angles are 27°. The P–O bond length is 1.49 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. In the second P5+ site, P5+ is bonded to one O2- and three Cl1- atoms to form PCl3O tetrahedra that share a cornercorner with one ReN2Cl3O octahedra. The corner-sharing octahedral tilt angles are 22°. The P–O bond length is 1.48 Å. There is one shorter (1.99 Å) and two longer (2.00 Å) P–Cl bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. In the second N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Re6+ and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Re6+ and one P5+ atom. There are twelve inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the eighth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the tenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the eleventh Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the twelfth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom.
BBr3PBr3 is Ammonia-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four boron tribromide molecules and four phosphorus tribromide molecules.
POBr3 is beta Np structured and crystallizes in the orthorhombic Pna2_1 space group. The structure is zero-dimensional and consists of four phosphorus oxybromide molecules. P5+ is bonded in a distorted tetrahedral geometry to one O2- and three Br1- atoms. The P–O bond length is 1.48 Å. There are two shorter (2.20 Å) and one longer (2.21 Å) P–Br bond lengths. O2- is bonded in a single-bond geometry to one P5+ atom. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one P5+ atom. In the second Br1- site, Br1- is bonded in a distorted single-bond geometry to one P5+ atom. In the third Br1- site, Br1- is bonded in a single-bond geometry to one P5+ atom.
This is the AmeriFlux version of the carbon flux data for the site US-ABc Archbold grazed improved pasture. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years, and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol
This is the AmeriFlux version of the carbon flux data for the site US-ABd Archbold ungrazed improved pasture. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years; and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol . Grazing was removed in 2013-2015 for the duration of the study
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ABc Archbold grazed improved pasture. This is the FLUXNET version of the carbon flux data for the site US-ABc Archbold grazed improved pasture produced by applying the standard ONEFlux (1F) software. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years, and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol
This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ABd Archbold ungrazed improved pasture. This is the FLUXNET version of the carbon flux data for the site US-ABd Archbold ungrazed improved pasture produced by applying the standard ONEFlux (1F) software. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years; and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol . Grazing was removed in 2013-2015 for the duration of the study
Nuclei are shown for the elements sodium, magnesium, aluminum, silicon, phosphorus, sulphur, chlorine, and argon. Individual nucleons are not identified as protons or neutrons. Nucleons are illustrated using a sphere schematic of the wave functions of singular, linear, and tetrahedral nucleon arrangements. Nucleon arrangements in protium, deuteron, triton, helion, and alpha are shown as building blocks in the nuclei of elements in the third period of the periodic table of elements.
The boson fermion nucleus (BFN) energy level is shown for sodium, magnesium, aluminum, silicon, phosphorus, sulphur, chlorine, and argon. The BFN energy levels are compared to the energy levels in the shell nuclear model. Individual nucleon fermions in the BFN make minor contributions to the nucleus energy level. Nucleons rearrange into boson structures during stellar nucleosynthesis and condense into the lowest-level energy state. Deconstruction of the BFN structure and conversion to a shell or liquid-drop model brings about a higher energy state. This is not favored in nature.
Our project has advanced the science of plant-soil-microbial dynamics across these areas: i) nutrient cycling and plant uptake; ii) root exudation and priming; and, iii) mycorrhizal dynamics. Our project has accomplished 5 main developments: 1) Incorporation of phosphorus cycling into the Fixation & Uptake of Nutrients (FUN 3.0) model. 2) Coupling of FUN 3.0 into the E3SM Land Model (ELM). 3) Data collection across a large mycorrhizal gradient in the US, as well data in the tropics, to parameterize, test, and validate the model. 4)Scaling up mycorrhizal association measurements across landscapes using airborne hyperspectral remote sensing data. 5) Evaluation of global carbon and nutrient cycle impacts in the Community Land Model (CLM5.0) from a suite of new global mycorrhizal association maps. Over 25 publications resulted from this project, with more continuing past the project funded lifetime. Paper highlights from most of these publications have already been submitted to the DOE paper submission online system. These publications include journals such as Science and PNAS, as well as top disciplinary journals from the Nature journals, Global Change Biology, New Phytologist, and Ecology Letters, for example. Our project also contributed to improving the process representation, capabilities, and accuracy of the DOE ELM. Overall, this project significantly advanced the science of belowground plant-soil-microbial interactions as well as technical capabilities from remote sensing to modeling.
Under this award, we synthesized and characterized new weakly coordinating, anionic covalent organic frameworks. The motivation was to expand the class of covalent organic frameworks though the introduction of the first weakly coordinating anionic ones. The significance of the weakly coordinating anionic character of these frameworks is associated with the character of the counter (metal) cations in their pores. Those counter-cations, due to the inability to effectively coordinate to the pore walls, have a “naked”, and thus highly electrophilic, Lewis acidic character. Such properties are expected to translate to a number of interesting physical properties that can be potentially used for a range of energy-relevant applications. One of these applications is gas adsorption, separation, and storage. The electrophilic, Lewis acidic character of the counter-cations are expected to strongly bind to gas molecules entering the pores leading to higher gas sorption capacities. Other applications include heterogeneous catalysis, ion exchange, and solid state ion conduction. Within the project we explored a range of chemical blocks, and tested synthesis conditions to polymerize these building blocks to form the target materials. In particular, we focused on materials with group 15 elements like phosphorus in the oxidation state +5 and the coordination number 6, that have a formal -1 charge. The synthesis of such materials is challenging because its success depends on the absence of residual monomeric and oligomeric side-products in the pores, and the absence of significant framework interpenetration. Crystalline forms of these materials require sufficient reversibility of the polymerization reaction (which is difficult to achieve because group 15 elements like P tend to make strong covalent bonds with neighbored elements), as well as suitable polymerization rates that prevent the formation of kinetically controlled products. We had success with the preparation of anionic porous organic frameworks with anionic building blocks containing P(V)O6 octahedra synthesized through Yamamoto coupling reactions. These materials are non-crystalline because of the irreversible nature of the Yamamoto coupling reaction, but show porosity. The porosity and surface area can be significantly increased by co-reaction with electrostatically neutral co-reactants. Very high porosity and surface areas can be achieved when the materials are washed with hydrochloric acid. This method is commonly used to free products from Yamamoto coupling reactions from by-products. Indeed, this method removed by products from the pores of our materials, however it also led to the hydrolysis of the PO6 octahedra to form pending phosphonic acid groups (-PO3H)-groups in the frameworks (PA-POFs) which was actually not desired. Nonetheless, these materials showed high CO2 sorption capacities. In addition, they show extremely high (actually record) sorption capacities for the removal of a range of common micropollutants such as bisphenol A (BPA) and 4-nitrophenol in water. BPA is a wide-spread organic pollutant and a known endocrine disruptor. The maximum adsorption capacity of BPA at equilibrium is found to be as high as 3,366 mg g-1 by Langmuir adsorption model, which is more than 10 times greater than peer materials. The polymer also rapidly removes various other organic micropollutants with more than 90% removal efficiencies. In addition, the PA-POF material can be regenerated at least five times by mild washing using methanol without significant loss in removal efficiency. This is significant advantage over commonly used activated carbon materials (that are in Brita water faucet filters, for example). Comparison studies showed that only materials with the phosphonate groups show extreme sorption although the number of PA group is actually small according to solid state NMR and EDX data. More research would be needed to investigate why this is (a possibility is that the phosphonate groups have a multiplying effect in which a PA-induced initial adsorption leads to the adsorption of much more adsorbate). The extreme sorption capabilities can also be visually seen when colored adsorbates such as 4-nitrophenol are used, as the adsorption of the nitrobenzene leads to the decoloration of the solution. We have produced three short videos that illustrate the sorption capabilities compared to two peer materials (activated carbon from dismantled Brita water filters, and a electrostatically neutral, chemically related, porous organic polymer, respectively).
Closing the fuel cycle is critical to the renaissance of nuclear energy in the United States. Essential in closing the fuel cycle is identification of separation strategies for actinides and fission products from spent fuels and identification of host matrices for storage or transmutation of fission products. These issues are intensified due to the complex nature of the problem (e.g., high radiation fields, high thermal fields, long half-lives of certain fission products). The use of extractor ligands with soft donor atoms has been demonstrated to selectively sequester actinides over their lanthanide counterparts. This has been presumed to be enhanced covalent bonding between the actinide 5f orbitals and the valence ligand-based orbitals; however, the coordination chemistry and reactivity with ligands containing selenium, tellurium, phosphorus, and arsenic are underdeveloped. Additionally, compounds containing actinide-ligand multiple bonding will be explored to examine pi-bonding with 5f orbitals. Efforts will be made to develop this chemistry with neptunium as well. This research explores the unique structure, bonding, and reactivity of the actinide elements while developing the underlying fundamental science involved in the separation of actinides.