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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
BN2(BH)4 is Cubic alpha N2-derived structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight 13730-91-1 molecules and thirty-two boranediylradical molecules.
CsLi(NH2)2 crystallizes in the hexagonal P6_222 space group. The structure is three-dimensional. Cs1+ is bonded in a 8-coordinate geometry to eight equivalent H1+ atoms. All Cs–H bond lengths are 3.40 Å. Li1+ is bonded to four equivalent N3- atoms to form distorted edge-sharing LiN4 trigonal pyramids. All Li–N bond lengths are 2.13 Å. N3- is bonded in a 2-coordinate geometry to two equivalent Li1+ and two equivalent H1+ atoms. Both N–H bond lengths are 1.03 Å. H1+ is bonded in a single-bond geometry to two equivalent Cs1+ and one N3- atom.
Sr(NH2)2 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Sr2+ is bonded in a 6-coordinate geometry to six equivalent N3- atoms. There are two shorter (2.65 Å) and four longer (2.76 Å) Sr–N bond lengths. N3- is bonded in a distorted water-like geometry to three equivalent Sr2+ and two equivalent H1+ atoms. Both N–H bond lengths are 1.03 Å. H1+ is bonded in a single-bond geometry to one N3- atom.
Yb(NH2)2 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Yb2+ is bonded in a 6-coordinate geometry to six equivalent N3- atoms. There are two shorter (2.44 Å) and four longer (2.56 Å) Yb–N bond lengths. N3- is bonded in a distorted water-like geometry to three equivalent Yb2+ and two equivalent H1+ atoms. Both N–H bond lengths are 1.03 Å. H1+ is bonded in a single-bond geometry to one N3- atom.
RbLi(NH2)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Rb1+ is bonded in a 8-coordinate geometry to two equivalent N3- and six H1+ atoms. Both Rb–N bond lengths are 2.96 Å. There are a spread of Rb–H bond distances ranging from 2.87–3.05 Å. Li1+ is bonded to four N3- atoms to form a mixture of distorted edge and corner-sharing LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.07–2.21 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a 2-coordinate geometry to three equivalent Li1+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N3- site, N3- is bonded in a distorted water-like geometry to two equivalent Rb1+, one Li1+, and two equivalent H1+ atoms. Both N–H bond lengths are 1.03 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to four equivalent Rb1+ and one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one Rb1+ and one N3- atom.
Ca(NH2)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four calcium;azanide molecules. Ca2+ is bonded in a 2-coordinate geometry to two N3- atoms. There are one shorter (2.45 Å) and one longer (2.49 Å) Ca–N bond lengths. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted water-like geometry to one Ca2+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N3- site, N3- is bonded in a distorted water-like geometry to one Ca2+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
Sr(NH2)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four strontium;azanide molecules. Sr2+ is bonded in a 2-coordinate geometry to two N3- atoms. There are one shorter (2.62 Å) and one longer (2.63 Å) Sr–N bond lengths. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted water-like geometry to one Sr2+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N3- site, N3- is bonded in a distorted water-like geometry to one Sr2+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
Mn(NH)2H2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional and consists of thirty-two hydrogen molecules and two Mn(NH)2 frameworks. In each Mn(NH)2 framework, Mn2+ is bonded in a distorted rectangular see-saw-like geometry to two N3- and two equivalent H1+ atoms. There are one shorter (2.03 Å) and one longer (2.09 Å) Mn–N bond lengths. There is one shorter (1.72 Å) and one longer (1.73 Å) Mn–H bond length. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded in a linear geometry to two equivalent N3- atoms. Both N–N bond lengths are 1.18 Å. In the second N3- site, N3- is bonded in a distorted water-like geometry to two equivalent Mn2+ and two equivalent H1+ atoms. Both N–H bond lengths are 1.03 Å. In the third N3- site, N3- is bonded in a bent 150 degrees geometry to one Mn2+ and one N3- atom. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a water-like geometry to two equivalent Mn2+ atoms. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
Zn(NH2)2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional and consists of two Zn(NH2)2 frameworks. Zn2+ is bonded to four N3- atoms to form corner-sharing ZnN4 tetrahedra. There are a spread of Zn–N bond distances ranging from 2.04–2.08 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to two equivalent Zn2+ and two H1+ atoms to form distorted corner-sharing NZn2H2 tetrahedra. Both N–H bond lengths are 1.02 Å. In the second N3- site, N3- is bonded in a distorted water-like geometry to two equivalent Zn2+ and two equivalent H1+ atoms. Both N–H bond lengths are 1.03 Å. In the third N3- site, N3- is bonded to two equivalent Zn2+ and two equivalent H1+ atoms to form distorted corner-sharing NZn2H2 tetrahedra. Both N–H bond lengths are 1.02 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
Be(NH2)2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional and consists of two Be(NH2)2 frameworks. Be2+ is bonded to four N3- atoms to form corner-sharing BeN4 tetrahedra. There are a spread of Be–N bond distances ranging from 1.74–1.79 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to two equivalent Be2+ and two H1+ atoms to form corner-sharing NBe2H2 tetrahedra. There is one shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the second N3- site, N3- is bonded to two equivalent Be2+ and two equivalent H1+ atoms to form corner-sharing NBe2H2 tetrahedra. Both N–H bond lengths are 1.02 Å. In the third N3- site, N3- is bonded to two equivalent Be2+ and two equivalent H1+ atoms to form distorted corner-sharing NBe2H2 tetrahedra. Both N–H bond lengths are 1.03 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
Mg(NH2)2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional and consists of two Mg(NH2)2 frameworks. Mg2+ is bonded to four N3- atoms to form corner-sharing MgN4 tetrahedra. There are a spread of Mg–N bond distances ranging from 2.09–2.12 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to two equivalent Mg2+ and two H1+ atoms to form distorted corner-sharing NMg2H2 tetrahedra. Both N–H bond lengths are 1.03 Å. In the second N3- site, N3- is bonded to two equivalent Mg2+ and two equivalent H1+ atoms to form distorted corner-sharing NMg2H2 tetrahedra. Both N–H bond lengths are 1.03 Å. In the third N3- site, N3- is bonded to two equivalent Mg2+ and two equivalent H1+ atoms to form distorted corner-sharing NMg2H2 tetrahedra. Both N–H bond lengths are 1.03 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
NiN2H4 crystallizes in the cubic Pm-3 space group. The structure is zero-dimensional and consists of three NiN2H4 clusters. there are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a rectangular see-saw-like geometry to four equivalent N3- atoms. All Ni–N bond lengths are 1.91 Å. In the second Ni2+ site, Ni2+ is bonded in a rectangular see-saw-like geometry to four N3- atoms. All Ni–N bond lengths are 1.92 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to two equivalent Ni2+ and two equivalent H1+ atoms to form distorted corner-sharing NNi2H2 tetrahedra. Both N–H bond lengths are 1.02 Å. In the second N3- site, N3- is bonded to two Ni2+ and two H1+ atoms to form distorted corner-sharing NNi2H2 tetrahedra. There is one shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the third N3- site, N3- is bonded to two equivalent Ni2+ and two equivalent H1+ atoms to form distorted corner-sharing NNi2H2 tetrahedra. Both N–H bond lengths are 1.02 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.
ZnTe(NH2)2(NH2)2 crystallizes in the monoclinic P2_1 space group. The structure is one-dimensional and consists of eight ammonia molecules and two ZnTe(NH2)2 ribbons oriented in the (1, 0, 0) direction. In each ZnTe(NH2)2 ribbon, there are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a distorted L-shaped geometry to two N3- and two Te4+ atoms. There are one shorter (2.13 Å) and one longer (2.14 Å) Zn–N bond lengths. There are one shorter (2.62 Å) and one longer (2.64 Å) Zn–Te bond lengths. In the second Zn2+ site, Zn2+ is bonded in a 4-coordinate geometry to two N3- and two Te4+ atoms. There are one shorter (2.13 Å) and one longer (2.15 Å) Zn–N bond lengths. There are one shorter (2.59 Å) and one longer (2.62 Å) Zn–Te bond lengths. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted water-like geometry to one Zn2+ and two H+0.75+ atoms. There is one shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. In the second N3- site, N3- is bonded in a distorted water-like geometry to one Zn2+ and two H+0.75+ atoms. Both N–H bond lengths are 1.03 Å. In the third N3- site, N3- is bonded in a distorted water-like geometry to one Zn2+ and two H+0.75+ atoms. There is one shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. In the fourth N3- site, N3- is bonded in a distorted water-like geometry to one Zn2+ and two H+0.75+ atoms. There is one shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. There are eight inequivalent H+0.75+ sites. In the first H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the second H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the third H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the fourth H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the fifth H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the sixth H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the seventh H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. In the eighth H+0.75+ site, H+0.75+ is bonded in a single-bond geometry to one N3- atom. There are two inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a water-like geometry to two Zn2+ atoms. In the second Te4+ site, Te4+ is bonded in a water-like geometry to two Zn2+ atoms.
The synthesis, characterization, theoretical calculations, and safety studies of energetic salts of 1,2- bis(oxyamino) ethane, (H2N-O-CH2-CH2-O-NH2), were carried out. The salts were characterized by vibrational (infrared, Raman), multinuclear nmr studies (1H, 13C), differential scanning calorimetry (DSC); elemental analysis; and initial safety testing (impact and friction sensitivity) . Theoretical calculations on the neutral, monoprotonated, and doubly protonated species of ethylene bisoxyamine were carried out using xxxx level of theory for the lowest energy structure and these theoretical results compared with the experimentally observed bond distances and vibrational (ir, Raman) frequency values. The single crystal X-ray diffraction study was carried out on the mono-perchlorate salt revealing a high degree of hydrogen bonding with an unexpected structure.
This work was motivated by the recommendations of the American Conference of Governmental Industrial Hygienists (ACGIH) that threshold limits for hydrazine, H2N-NH2 in air be lowered from 100 to 10 parts-per-billion (ppb) concentration levels. Hydrazine is one of the high-energy propellants used in large volumes in Space Shuttle, Titan, payloads, and other aerospace operations. Since analytical methods presently available for hydrazine detection and/or determination do not satisfy such low levels of detection, the ultimate goal of this research is the development and characterization of a portable and compact chemical sensor ideally capable to detect (in real time) 1 ppb of hydrazine, continuously and reversibly. The laboratory prototype developed as part of this project is comprised of: (1) a reactor part in which H2N-NH2 reacts, generating chemiluminescence emission, with tris(2,2'-bipyridine)ruthenium(III), which is immobilized on an ion-exchange polymeric materials of a perfluorinated hydrocarbon containing sulfonate groups as exchange centers (Nafion); (2) an electrochemical three-electrode cell posed at a potential at which the immobilized ruthenium complex could be reoxidized to the 3-oxidation state (as to provide reversible and continuous detection); and (3) a low power consumption photomultiplier tube to collect and quantitatively integrate the emitted photons with the help of auxiliary electronics and readout device.
New crosslinked 1,2,4-oxadiazole elastomers were prepared by thermally condensing a monomer having the formula H2N(HON)C-R-Q, wherein Q is a triazine ring-forming group such as nitrile or amidine or a mixture of such group with amidoxime, or a mixture of said monomer with R C(NOH)NH2 sub 2 with R in these formulas standing for a bivalent organic radical. In the monomer charge, the overall proportions of amidoxime groups to triazine ring-forming groups varies depending on the extent of crosslinking desired in the final polymer.
The preparation of crosslinked 1,2,4-oxadiazole elastomers is described. The technique involves thermally condensing (1) a monomer having the formula H2N(HON)C-R-Q, wherein Q is a triazine ring-forming groups such as nitrile or amidine or a mixture of such group with amidoxime, or (2) a mixture of the same monomer with R(C(NOH)NH2)2, with R in these formulas standing for a bivalent organic radical. In the monomer charge, the overall proportions of amidoxime groups to triazine ring-forming groups varies depending on the extent of crosslinking desired in the final polymer.