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The crystal structure of bis-muth penta-fluoride, BiF5, was rerefined from single-crystal data. BiF5 crystallizes in the α-UF5 structure type in the form of colorless needles. In comparison with the previously reported crystal-structure model [Hebecker (1971 â¸). Z. Anorg. Allg. Chem. 384, 111-114], the lattice parameters and fractional atomic coordinates were determined to much higher precision and all atoms were refined anisotropically, leading to a significantly improved structure model. The Bi atom (site symmetry 4/m..) is surrounded by six F atoms in a distorted octa-hedral coordination environment. The [BiF6] octa-hedra are corner-linked to form infinite straight chains extending parallel to [001]. Density functional theory (DFT) calculations at the PBE0/TZVP level of theory were performed on the crystal structure of BiF5 to calculate its IR and Raman spectra. These are compared with experimental data.
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Administrative burden across state-federal benefits programs is unsustainable, and artificial intelligence (AI) and associated technologies have emerged and resulted in significant interest as possible solutions. While early in development, AI has significant potential to reduce administrative waste and increase efficiency, with many government agencies and state legislators eager to adopt the new technology. Turning to existing frameworks defining what functions are considered "inherently governmental" can help determine where more autonomous implementation could be not only appropriate but also provide unique advantages. Such areas could include eligibility and redetermination of Medicaid eligibility as well as preventing improper Medicaid payments. However, while AI is promising, this technology may not be ready for fully autonomous implementation and instead could be deployed to augment human capabilities with robust safeguards until it has proven to be more reliable. In the meantime, the Centers for Medicare and Medicaid Services should release clear guidance around the use of AI by state Medicaid programs, and policymakers must work together to harness AI technologies in order to improve the efficiency and effectiveness of the Medicaid program.
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Greater attention is being paid to the transition to adulthood for youth with disabilities. We are also at a period of reckoning with the vestiges of slavery, Jim Crow, and a lack of constitutional protections for Black-identifying persons. The contemporary impact of inequitable access to opportunities, services, and supports that would improve the quality of life of racialized Black individuals has added consequences for Black youth with disabilities. A sub-population of youth with disabilities receives monthly support in the form of Supplemental Security Income (SSI), with a disproportionate number of Black-identifying youth qualifying for SSI. Such youth are impacted by the intersectionality of racism, disability, and poverty. The outcome of an SSI age-18 redetermination can be precarious and occurs in the backdrop of these intersectional forces, impacting the life course of racialized Black youth and their families on a scale that is concerning. The authors describe the time frames of pre age-18 redetermination, age-18 redetermination and post age-18 redetermination in the contexts of intersectionality and transition, and articulate what type of services and supports can reduce the experience of chronic stress in the lives of racialized Black youth facing an SSI age-18 redetermination, and thereby improve the outcomes of these youth as they transition to adulthood.
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The structure of the dimeric title compound, [Sn2(C4H9)4Cl2(OH)2], was redetermined at 100â K by use of an area detector to provide new data to improve the structural parameters for detailed analysis. Noteworthy is the folding of the central, non-symmetric, four-membered [SnO]2 ring [dihedral angle about the Oâ¯O axis = 1.09â (3)°], as well as the elongation of the Sn-Cl bonds [mean value = 2.5096â (4)â Å], as a result of inter-molecular O-Hâ¯Cl hydrogen bonds; the latter lead to a chain-like arrangement of dimeric mol-ecules along [101].
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Single crystals of NbF5, niobium(V) fluoride, have been obtained by the reaction of niobium metal in a stream of dilute elemental fluorine at 473â K and subsequent sublimation. The as-obtained bulk phase compound was shown to be pure by powder X-ray diffraction at 293â K and by IR and Raman spectroscopy. A single-crystal X-ray analysis was conducted at 100â K. In comparison to the previously reported structure model [Edwards (1964 â¸). J. Chem. Soc. pp. 3714-3718], the lattice parameters and fractional atom coordinates were determined to much higher precision and individual, anisotropic displacement parameters were refined for all atoms.
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A djurleite crystal was discovered from a natural sample originally labelled as chalcocite. The djurleite crystal under investigation has a refined composition of Cu61.39S32, thus revealing a Cu deficiency compared to the originally reported Cu62S32 phase [Evans (1979). Z. Kristallogr. 150, 299-320], where all atomic sites are reported to be fully occupied. In addition, the current refinement revealed a splitting of eight of the Cu sites into pairs.
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The reaction of ß-(thio-morpholin-1-yl)propio-amidoxime with tosyl chloride in CHCl3 in the presence of DIPEA when heated at 343â K for 8â h afforded the title hydrated salt, C7H14N3S+·Cl-·H2O, in 84% yield. This course of the tosyl-ation reaction differs from the result of tosyl-ation obtained for this substrate at room temperature, when only 2-amino-8-thia-1,5-di-aza-spiro-[4.5]dec-1-ene-5-ammonium tosyl-ate was isolated in 56% yield. The structure of the reaction product was established by physicochemical methods, spectroscopy, and X-ray diffraction. The single-crystal data demonstrated that the previously reported crystal structure of this compound [Kayukova et al. (2021). Chem. J. Kaz, 74, 21-31] had been refined in a wrong space group. In the extended structure, the chloride anions, water mol-ecules and amine groups of the cations form two-periodic hydrogen-bonded networks with the fes topology.
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Medicaid beneficiaries in most states must go through a redetermination process every 6-12 months to demonstrate continued eligibility. This study sought to examine Medicaid redetermination experiences among beneficiaries with Limited English Proficiency (LEP). A sequential mixed methods study was conducted involving quantitative phone surveys and semi-structured, in-person interviews with Arabic, Chinese, Korean, and Vietnamese speaking beneficiaries in Illinois. Survey respondents experienced notable barriers during the redetermination process. Quantitative data showed LEP respondents to have 5.3 times the odds of losing their Medicaid benefits as compared to English proficient respondents. Qualitative interviews illustrated the impact of Medicaid loss on individuals and families, as well as strategies for successfully navigating redetermination. Findings suggest that language barriers hinder Medicaid redetermination and play a role in cancellation of benefits. Recommendations for better language supports during the Medicaid redetermination process are discussed.
Subject(s)
Limited English Proficiency , Communication Barriers , Humans , Illinois , Language , Medicaid , United StatesABSTRACT
The crystal structure model for potassium tri-iodido-mercurate(II) monohydrate, K[HgI3]·H2O, based on single-crystal data, was reported 50 years ago [Nyqvist & Johansson (1971 â¸). Acta Chem. Scand. 25, 1615-1629]. We have now redetermined this structure with X-ray diffraction data at 0.70â Å resolution collected at 153â K using Ag Kα radiation. Combined quantum mechanical methods (ORCA) and computation of non-spherical scattering form factors (NoSpherA2) allowed the refinement of the shape of the water mol-ecule with anisotropic H atoms, despite the presence of heavy elements in the crystal. The refined shape of the water mol-ecule via this Hirshfeld refinement is close to that determined for liquid water by neutron diffraction experiments. Moreover, the Laplacian of the electron density clearly shows how electron density accumulates along the O-H σ-valence bonds in the water mol-ecule.
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In comparison with the previous structure determination of K2Mg3(OH)2(SO4)3(H2O)2, dipotassium trimagnesium di-hydroxide tris-(sulfate) dihydrate, from laboratory powder X-ray diffraction data [Kubel & Cabaret-Lampin (2013 â¸). Z. Anorg. Allg. Chem. 639, 1782-1786], the present redetermination against CCD single-crystal data has allowed for the modelling of all non-H atoms with anisotropic displacement parameters. As well as higher accuracy and precision in terms of bond lengths and angles, the clear localization of the H-atom positions leads also to a reasonable hydrogen-bonding scheme for this hy-droxy hydrate. The structure consists of (100) sheets composed of corner- and edge-sharing [MgO6] octa-hedra and sulfate tetra-hedra. Adjacent sheets are linked by the potassium cations and a hydrogen bond of medium strength involving the water mol-ecule. The title compound is isotypic with its CoII and MnII analogues: the three K2 M 3(OH)2(SO4)3(H2O)2 (M = Mg, Co, Mn) structures are qu-anti-tatively compared.
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The crystal structure of oxido-nitro-gen(1+) tetra-fluorido-borate (nitro-sonium tetra-fluorido-borate), NO+BF4 -, was refined on the basis of single-crystal X-ray diffraction data at 150â K. The compound crystallizes in the baryte structure type with ortho-rhom-bic Pnma symmetry. The crystal structure exhibits cationic disorder with equal occupation of N and O atoms at the same site.
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The structures of tolfenamic acid [TFA; 2-(3-chloro-2-methyl-anilino)benzoic acid, C14H12ClNO2] polymorph forms I and II have been redetermined [compare Andersen et al. (1989 â¸). J. Chem. Soc., Perkin Trans. 2, pp. 1443-1447] with improved precision using high-resolution X-ray diffraction data and Hirshfield atom refinement in order to better define both hydrogen-atom locations and their associated bond lengths. Covalent bond lengths to hydrogen were found to be significantly longer throughout both structures, especially for the anilino H atom, which is involved in an important intra-molecular N-Hâ¯O hydrogen bond to the carb-oxy-lic acid group. This hydrogen bond is shown to clearly perturb the electron density around both oxygen atoms in the latter group. The extended structures of both polymorphs feature carb-oxy-lic acid inversion dimers. These structures provide an improved foundation for nuclear magnetic resonance studies in both solution and the solid state.
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The title compounds, 2-(ferrocenylcarbon-yl)benzoic acid, [Fe(C5H5)(C13H9O3)], 1, and 3-ferrocenylphthalide [systematic name: 3-ferrocenyl-2-benzo-furan-1(3H)-one], [Fe(C5H5)(C13H9O2)], 2, have been synthesized and structurally characterized by single-crystal X-ray diffraction. The crystal structure of compound 1 was solved recently at room temperature [Qin, Y. (2019 â¸). CSD Communication (CCDC deposition number 1912662). CCDC, Cambridge, England]. Here we report a redetermination of its crystal structure at 90â K with improved precision by a factor of about three. The mol-ecular structures of both compounds exhibit a typical sandwich structure. In the crystal packing of compound 1, each mol-ecule engages in inter-molecular hydrogen bonding, forming a centrosymmetric dimer with graph-set notation R 2 2 (8) and an Oâ¯O distance of 2.6073â (15)â Å. There are weak C-Hâ¯O and C-Hâ¯π inter-actions in the crystal packing of compound 2. The phthalide moiety in 2 is oriented roughly perpendicular to the ferrocene backbone, with a dihedral angle of 77.4â (2)°.
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The crystal structure of vanthoffite {hexa-sodium magnesium tetra-kis[sulfate-(VI)]}, Na6Mg(SO4)4, was solved in the year 1964 on a synthetic sample [Fischer & Hellner (1964 â¸). Acta Cryst. 17, 1613]. Here we report a redetermination of its crystal structure on a mineral sample with improved precision. It was refined in the space group P21/c from a crystal originating from Surtsey, Iceland. The unique Mg (site symmetry ) and the two S atoms are in usual, only slightly distorted octa-hedral and tetra-hedral coordinations, respectively. The three independent Na atoms are in a distorted octa-hedral coordination (1×) and distorted 7-coordinations inter-mediate between a 'split octa-hedron' and a penta-gonal bipyramid (2×). [MgO6] coordination polyhedra inter-change with one half of the sulfate tetra-hedra in <011> chains forming a (100) meshed layer, with dimers formed by edge-sharing [NaO7] polyhedra filling the inter-chain spaces. The other [NaO7] polyhedra are organized in a parallel layer formed by [010] and [001] chains united through edge sharing and bonds to the remaining half of sulfate groups and to [NaO6] octa-hedra. The two types of layers inter-connect through tight bonding, which explains the lack of morphological characteristics typical of layered structures.
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Caesium tetra-fluorido-bromate(III), CsBrF4, was crystallized in form of small blocks by melting and recrystallization. The crystal structure of CsBrF4 was redetermined from single-crystal X-ray diffraction data. In comparison with a previous study based on powder X-ray diffraction data [Ivlev et al. (2013 â¸). Z. Anorg. Allg. Chem. 639, 2846-2850], bond lengths and angles were determined with higher precision, and all atoms were refined with anisotropic displacement parameters. It was confirmed that the structure of CsBrF4 contains two square-planar [BrF4]- anions each with point group symmetry mmm, and a caesium cation (site symmetry mm2) that is coordinated by twelve fluorine atoms, forming an anti-cubocta-hedron. CsBrF4 is isotypic with CsAuF4.
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The crystal structure of (NH4)2V3O8 has been reported twice using single-crystal X-ray data [Theobald et al. (1984 â¸). J. Phys. Chem. Solids, 45, 581-587; Range et al. (1988 â¸). Z. Naturforsch. Teil B, 43, 309-317]. In both cases, the orientation of the ammonium cation in the asymmetric unit was poorly defined: in Theobald's study, the shape and dimensions were constrained for NH4 +, while in Range's study, H atoms were not included. In the present study, we collected a highly redundant data set for this ternary oxide, at 0.61â Å resolution, using Ag Kα radiation. These accurate data reveal that the NH4 + cation is disordered by rotation around a non-crystallographic axis. The rotation axis coincides with one N-H bond lying in the mirror m symmetry element of space-group type P4bm, and the remaining H sites were modelled over two disordered positions, with equal occupancy. It therefore follows that the NH4 + cations filling the space available in the (001) layered structure formed by (V3O8)2- ions do not form strong N-Hâ¯O hydrogen bonds with the mixed-valent oxidovanadate(IV,V) anions. This feature could have consequences for the Li-ion inter-calation properties of this material, which is used as a cathode for supercapacitors.
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After crystallization during ionothermal syntheses in phospho-nium-containing ionic liquids, the structure of (NH4)3Al2(PO4)3 [tri-ammonium dialuminum tris-(phosphate)] was refined on the basis of powder X-ray diffraction data from a synchrotron source. (NH4)3Al2(PO4)3 is a member of the structural family with formula A 3Al2(PO4)3, where A is a group 1 element, and of which the NH4, K, and Rb forms were previously known. The NH4 form is isostructural with the K form, and was previously solved from single-crystal X-ray data when the material (SIZ-2) crystallized from a choline-containing eutectic mixture [Cooper et al. (2004 â¸). Nature, 430, 1012-1017]. Our independent refinement incorporates NH4 groups and shows that these NH4 groups are hydrogen bonded to framework O atoms present in rings containing 12 T sites in a channel along the c-axis direction. We describe structural details of (NH4)3Al2(PO4)3 and discuss differences with respect to isostructural forms.
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The crystal structure of [ZnCl2(NH3)2], diamminedi-chlorido-zinc, was re-investigated at low temperature, revealing the positions of the hydrogen atoms and thus a deeper insight into the hydrogen-bonding scheme in the crystal packing. In comparison with previous crystal structure determinations [MacGillavry & Bijvoet (1936 â¸). Z. Kristallogr. 94, 249-255; Yamaguchi & Lindqvist (1981 â¸). Acta Chem. Scand. 35, 727-728], an improved precision of the structural parameters was achieved. In the crystal, tetra-hedral [Zn(NH3)2Cl2] units (point-group symmetry mm2) are linked through N-Hâ¯Cl hydrogen bonds into a three-dimensional network.
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Presented herein is the crystal-structure redetermination of Li4ZrF8 from single-crystal X-ray data. Alkali zirconium fluorides are important in nuclear-relevant technologies, and zirconium is commonly employed as an analogue for tetra-valent f-block elements. The previous structure report of this species is based on powder X-ray data [Dugat et al. (1995 â¸). J. Solid State Chem. 120, 187-196] but there has never been a refined structure model from single-crystal data. The octa-fluorido-zirconate moieties are held together by electrostatic attraction to lithium ions without sharing of fluoride sites between zirconium(IV) ions.
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A re-investigation of the crystal structure of tricalcium cobalt(II) tetra-aluminate, Ca3CoAl4O10, using single-crystal X-ray diffraction data, revealed ortho-rhom-bic (Pbcm) symmetry. The present contribution corrects the results of a previous X-ray powder diffraction study [Vazquez et al. (2002 â¸). J. Solid State Chem. 166, 191-196] where this phase has been described in an unnecessarily low space-group symmetry (Pbc21). The compound belongs to the group of tetra-hedral framework structures. The distribution of the aluminium and cobalt ions among the centres of the four different tetra-hedra within the asymmetric unit has been studied in detail. Charge compensation is achieved by the incorporation of two symmetrically independent calcium ions located in voids of the tetra-hedral framework. Ca3CoAl4O10 is isotypic with Ca3MgAl4O10.