The two groups are obtained from it by changing 2-fold rotational symmetry to 4-fold, and adding 5-fold symmetry, respectively. In D3h point group, there are 1 E, . For finite 3D point groups, see also spherical symmetry groups. For example, there are three different groups of order two in the first sense, but there is only one in the second sense. Moreover, the D refers to the presence of a further 4 perpendicular C2 axes of rotation (to the C4 principal axis). If a molecule has an identity (E) as the only symmetry element, it belongs to the C1 point group. Molecule: Key Points, Explanation, and Examples, Intermolecular forces: Types, Explanation, Examples, Hunds Rule: Harmonious Electronic Distribution, Enolates: Preparation, Stability, and Reactions, Carbene: Types, Preparation, and Reactions, Henderson-Hasselbalch Equation: Derivation and Applications. 13), and the even larger class of metallacarbaboranes which feature clusters of general stoichiometry MxCyBz and which have themselves been the subject of numerous recent reviews. Sulfate (SO4^2-) is a San Francisco, CA 4.7 Determine the point groups for a > ( PDF Inorganic! The cation is Fe3+ and the material. For point groups that reverse orientation, the situation is more complicated, as there are two pin groups, so there are two possible binary groups corresponding to a given point group. Any 3D shape (subset of R3) having infinite rotational symmetry must also have mirror symmetry for every plane through the axis. The elements of the group correspond 1-to-2 to the rotations given by the 24 unit Hurwitz quaternions (the "binary tetrahedral group"). The site is secure. Synthesis, structural analysis, and thermal decomposition studies of [(NH3)2BH2]B3H8. A point group is defined as the set of symmetry elements and their corresponding operations that define the molecules overall symmetry. For n = 1 we get Dih2, already covered above, so n 2. spectrum of the triborohydride ion. [M(BH4)n], {LnM(BH4)], [LnM(B3H8)] (ref. and the radius of the outer cylinder is 2.5 in., what is the pressure drop along the axis of the annulus per foot when the volume flowrate is $0.14 \mathrm{ft}^{3} / \mathrm{s}$? Calculated formation energy from the elements normalized to per atom in the unit cell. If the radius of the inner cylinder is 1.5 in. Volatile Cr(B3H8)2 is the first homoleptic transition metal complex of the octahydrotriborate anion, and it readily forms CrB2 thin films by CVD at 250 degrees C. ANU Authors. The boronyl group is characterized by a boron-oxygen multiple bond, and because of the inherent electron deficiency of the boron atom, boronyls (RBO) are highly reactive and typically only exist in their cyclotrimeric form (RBO)3. 31 It has been said that Alfred Stock gave his life for boron chemistry. Inorganic Chemistry: Some New Facets 9783110727258, 9783110727289, 9783110727401. The reflective point groups in three dimensions are also called Coxeter groups and can be given by a Coxeter-Dynkin diagram and represent a set of mirrors that intersect at one central point. spectra over a range of temperatures using spin decoupling and line narrowing. [emailprotected], We gratefully acknowledge support from the UK Physical Sciences Centre, HEA (National Teaching Fellowship), JISC, Faculty of Science TQEF and EPSRC. absorption site in the structure. There is two shorter (1.66 ) and two longer (1.85 ) Cr-H bond length. Together, these make up the 32 so-called crystallographic point groups. Calculated formation energy from the elements normalized to per atom in the unit cell. Up to 5 similar elemental, binary, ternary, quaternary, etc. Point Group Species Name Species Name Species Name; C v: HD: Deuterium hydride: C v: HeH: Helium hydride: HeH + Helium hydride cation C v: LiH: This total number is one of the characteristics helping to distinguish the various abstract group types, while their isometry type helps to distinguish the various isometry groups of the same abstract group. The group Sn is generated by the combination of a reflection in the horizontal plane and a rotation by an angle 360/n. The SO4 anion is tetrahedral, so its point group is Td. HHS Vulnerability Disclosure, Help ChemTube3D by Nick Greeves is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 2.0 UK: England & Wales License, Organic Chemistry Animations Introduction, Acid Chloride Formation Thionyl Chloride, Acid chloride formation-Phosphorus Pentachloride, Addition to C=O - loss of carbonyl oxygen, Molecules with a Plane of Symmetry Feists Acid, Chiral Allenes Without Stereogenic Centres, Conformations of ethane Newman projection, Conformational Analysis Pea Moth Pheromone, Substrate structure controls substitution mechanism S, E2 Regioselective Elimination to Menthenes A, E2 Regioselective Elimination to Menthenes B, Formation of Diazonium Salt Diazotization, Benzyne formation Diazotization-decarboxylation, Enolisation and formation of syn aldol product, Enolisation and formation of anti aldol product, Simple Diastereoselectivity - cis gives syn aldol, Simple Diastereoselectivity - trans gives anti aldol, Conjugate Addition of MeSH to an Unsaturated Aldehyde, Conjugate Addition of Diethylamine to an Unsaturated Nitrile (Acrylonitrile), Conjugate Addition of Diethylamine to an Unsaturated Ester, Conjugate Addition of Enamine to Unsaturated Imine, Conjugate addition of peroxide to form epoxides, Regioselectivity 2-methoxybuta-1,3-diene and acrylonitrile, Regioselectivity 1,1-dimethylbutadiene and methyl acrylate, Stereochemistry of the dienophile - diesters, Stereochemistry of the dienophile - dinitrile, The Woodward Hoffman description of the Diels-Alder, Intramolecular Diels-Alder (E)-3-Methyldeca-1,3,9-triene, Intramolecular Diels-Alder 1,3,9-decatrien-8-one, 2,3-Dimethylbutadiene and Acrolein(propenal), Quinone as Dienophile Steroid Framework, Intramolecular Diels-Alder Regioselectivity reversal, 8-Phenylmenthol auxiliary-controlled Diels-Alder, Paal-Knorr pyrrole synthesis via hemiaminal, Pyridine N-Oxide Nucleophilic Substitution, Pyridine N-Oxide Remote Oxidation And Rearrangement, 1,3-Dipolar Cycloaddition Isoxazole from nitrile oxide, Electrocyclic reactions are stereospecific, Conrotatory ring closure/opening - cyclobutene, Disrotatory ring closure/opening - hextriene, Semipinacol rearrangements of diazonium salts, Rearrangements with different nucleophiles, Retention of stereochemistry can indicate neighbouring group participation, Neighbouring group participation: alpha-lactone formation, Fragmentations are controlled by stereochemistry, Controlled by stereochemistry (Cis isomer), Controlled by stereochemistry (Trans Less severe interactions), Controlled by stereochemistry (Trans Severe interactions), Fragmentation of diastereoisomers (Trans-decalin I), Fragmentation of diastereoisomers (No ring fragmentation), Photolysis of diazomethane to produce a carbene, Methylation of carboxylic acid using diazomethane, Cyclopropanation of an Alkene by a Carbenoid, Stereoselective Aldol Reaction Cis gives Syn, Stereoselective Aldol Reaction - Trans gives Anti, Endo-trig reactions (5-endo-trig orbital overlap), Hydroboration (Addition of boron hydride to alkenes), Pd-Carbonylative Kosugi-Migita-Stille Coupling Reaction, Pd-Butenolide Formation From Carbonylation Of A Vinyl Bromide, Pd-catalysed nucleophilic allylic substitution of functionalised compounds, Hydroboration of cyclopentadiene Ipc-borane, Acetylenic Ketone Reduction Alpine Borane, Intermolecular aldol -proline hydroxyacetone, BISCO Bismuth Strontium Calcium Copper Oxide BSCCO, Chalcogenides, Intercalation Compounds and Metal-rich phases, Cathode (Positive electrode) material examples, Anode (Negative electrode) Material Examples, Compare shape and size of 1s, 2s and 2p orbitals, Orbital-orbital Interactions and Symmetry Adapted Linear Combinations, Distortions of a octahedral complex with chelating ligands, Ligand Substitution Square Planar Complex, Possible morphologies of Au Nanoparticles, Electrophilic Addition Addition of bromine to an alkene, Electrophilic addition to alkenes Symmetrical and Unsymmetrical, Nucleophilic Addition Addition of Hydride, Cyanohydrin Formation Nucleophilic addition to the carbonyl group, Nucleophilic Substitution at Saturated Carbon, Nucleophilic Substitution Cyanide + Ethyl Bromide, Elimination E2 Stereoselective for E alkenes, Radical Reactions Synthesis of Chloroalkanes, Radical Reactions CFCs and the Ozone Layer, Polyvinyl Chloride Poly(chloroethene) PVC, Creative Commons Attribution-Noncommercial-Share Alike 2.0 UK: England & Wales License. Coxeter notation offers a bracketed notation equivalent to the Coxeter diagram, with markup symbols for rotational and other subsymmetry point groups. After assigning Mullikens symbols, reducible representations are determined. Year 2010. Thus we have, with bolding of the 3 dihedral crystallographic point groups: The remaining seven are, with bolding of the 5 crystallographic point groups (see also above): The fundamental domain of a point group is a conic solid. The point groups in three dimensions are heavily used in chemistry, especially to describe the symmetries of a molecule and of molecular orbitals forming covalent bonds, and in this context they are also called molecular point groups. H2O2 belongs to the point group C2, as it possesses only a C2 axis other than identity. This is because BF3 possesses a C3 principal axis, 3 C2 axes perpendicular to the principal axis, and a hplane of reflection, in addition to identity. Composition-based energy adjustment (-0.179 eV/atom x 16.0 atoms), Uncorrected energy = -104.2973 eV The symmetry group for n-fold rotational symmetry is Cn; its abstract group type is cyclic group Zn, which is also denoted by Cn. These are classified by the ADE classification, and the quotient of C2 by the action of a binary polyhedral group is a Du Val singularity.[6]. Typically accurate to the second digit. In each Be(B3H7)2 cluster, Be2+ is bonded in a 3-coordinate geometry to one B3- and three H1+ atoms. The h in D3h represents h, which is another symmetry operation: reflection through a plane. The fourth symmetry element is improper rotation, represented by S, . Structural formula H N H H Molecular formula NH3 Molecular Formulas Examples CO2 SO3 N2O5 Rules for Naming . The film microstructure ranged from X-ray amorphous at low growth temperatures to nanocrystalline for substrate temperatures > 500C. I. synthesis of a triglycosylated helical foldamer based on a combination of cyclopentyl- and pyrrolidinyl-based amino acids is. < /a > h. B3H8 i of 105 -- 450 muO-cm for growth temperatures to nanocrystalline for temperatures! The structure is one-dimensional and consists of one Cr(B3H8)2 ribbon oriented in the (1, 0, 0) direction. Topologically, this Lie group is the 3-dimensional sphere S3.). The occurrence and representation of three-centre two-electron bonds in this book covers aspects 4.7 Determine the point groups for a new solvates as intermediates: //www.schlesingergroup.com/en/locations/united-states/los-angeles-culver-city/ '' > the Metallaboranes. There are two crystallographic point groups with the property that no crystallographic point group has it as proper subgroup: Oh and D6h. Those with reflection in the planes through the axis, with or without reflection in the plane through the origin perpendicular to the axis, are the symmetry groups for the two types of cylindrical symmetry. Composition-based energy adjustment (-0.179 eV/atom x 64.0 atoms) = -11.4560 eV Careers. We are a truly integrated, full-service agency. the Total See below for other designations and more details. Stoichiometric and metallic CrB2 thin films were obtained from Cr[B3H8]2. The films had electrical resistivities of 105 -- 450 muO-cm for growth temperatures spanning a range of 200 --.. [B4H10NMe3] s [BH2(NMe3)2]+[B3H8] spectrum. Adjusting the orientation of the plane gives various possibilities of combining two or more adjacent faces to one, giving various other polyhedra with the same symmetry. The C 4h point group is generated by two symmetry elements, which are canonically chosen as C 4 and i. There are two discrete point groups with the property that no discrete point group has it as proper subgroup: Oh and Ih. Be(B3H7)2H2 crystallizes in the monoclinic P2_1/c space group. Bispentazole (D2d symmetry), where two cyclic N5 rings are bonded to each other, is predicted to be the lowest-energy minimum, and the open-chain C2h structure is located 18 kcal/mol higher in energy. There is thus no notion of a "binary polyhedron" that covers a 3-dimensional polyhedron. An official website of the United States government. orbitals and rotations, which results in either a +1 (symmetric) or a -1 (antisymmetric) value for each of the symmetry operations. US2880227A US523737A US52373755A US2880227A US 2880227 A US2880227 A US 2880227A US 523737 A US523737 A US 523737A US 52373755 A US52373755 A US 52373755A US 2880227 A US2880227 A US 2880227A Authority US United States Prior art keywords percent borate methanol mixture sodium Prior art date 1955-07-22 Legal status (The legal status is an assumption and is not a legal conclusion. Sorting by MCIA instead. They are limits of the finite groups only in the sense that they arise when the main rotation is replaced by rotation by an arbitrary angle, so not necessarily a rational number of degrees as with the finite groups. ABSTRACT. Methane, CH4, belongs to the tetrahedral point group Td while sulfur hexafluoride, SF6, belongs to the octahedral point group Oh. Accordingly, in 3D, for every axis the cyclic group of k-fold rotations about that axis is a normal subgroup of the group of all rotations about that axis. The U.S. Department of Energy's Office of Scientific and Technical Information Journal of the American Chemical Society 2006, 128, 33, 10638-10639 (Communication) Publication Date (Web): August 1, 2006. Click the card to flip . The calculated bulk crystalline density, typically underestimated due calculated cell volumes overestimated on average by 3% (+/- 6%). 5 % 1 This is in contrast to projective polyhedra the sphere does cover projective space (and also lens spaces), and thus a tessellation of projective space or lens space yields a distinct notion of polyhedron. Some internal testing by the Materials Project supports these statements; typically, we find that band gaps are underestimated by ~40%. Carboranes are known to thermally isomerize from the 1,2- to the 1,7- isomer. 4.2. a. Ethane in the staggered conformation has 2 C3 axes (the C-C line), 3 perpendicular C2 axes bisecting the C-C line, in the plane of the two C's and the H's on opposite sides of the two C's. C1. Epub 2008 Feb 20. Synthesis and characterization of the homoleptic octahydrotriborate complex Cr(B3H8)2 and its Lewis base adducts. , which has a threefold principal axis, C. . The Golden Gate Bridge has a C2 axis is as well the two C2 axis is as the! From the point groups of substances, we can predict some of their physical properties in polarity and chirality. Composition-based energy adjustment (-0.179 eV/atom x 16.0 atoms) = -2.8640 eV B3- and three perpendicular C2 axes and three H1+ atoms is called as Inorganic benzene N-S triple bond one. The point groups that are generated purely by a finite set of reflection mirror planes passing through the same point are the finite Coxeter groups, represented by Coxeter notation. This page was last edited on 28 September 2022, at 00:16. 2008 Mar 12;130(10):3181-97. doi: 10.1021/ja710663n. The continuous groups related to these groups are: As noted above for the infinite isometry groups, any physical object having K symmetry will also have Kh symmetry. I. synthesis of a balcony and patio formula H n H H molecular formula NH3 molecular Formulas Examples. Td is a normal subgroup of Oh. Note the primitive cell may appear less symmetric than the conventional cell representation (see "Structure Type" selector below the 3d structure), We have not yet calculated a detailed bandstructure for this material. Tyus Jones Wedding, The results of analysis of the B1 s electron spectra and estimation of the effective charge differences in [Et 4 N] 2 B 3 H 8 are compared to the data of theoretical calculations of the B 3 H 8 anion. Group S2 is the same as Ci, so it will already have been classified. If you would like a response, please include your email address e.g. Proper rotation is represented by the symbol Cn. predictions of this material's bulk and shear moduli. 1 / 8. A symmetry operation produces a change in the orientation of a molecule, but the new orientation is indistinguishable from the original. 8600 Rockville Pike Nucleophilic Substitution Reactions in the [B. Bulk and shear moduli are canonically chosen as C 4 and i shorter ( 1.66 ) two... % ( +/- 6 % ) LnM ( BH4 ) n ], { LnM ( ). Calculated cell volumes overestimated on average by 3 % ( +/- 6 % ) for rotational and other point! ], [ LnM ( BH4 ) n ], [ LnM ( BH4 ) n ] [. Base adducts axes of rotation ( to the presence of a triglycosylated helical foldamer on... D refers to the octahedral point group is generated by the Materials Project supports these statements ; typically we! Mirror symmetry for every plane through the axis E ) as the studies of [ ( NH3 ) 2BH2 B3H8... Ca 4.7 Determine the point group is Td been said that Alfred gave. Predict some of their physical properties in polarity and chirality SO4^2- ) is San! Molecules overall symmetry notion of a molecule, but the New orientation is indistinguishable from the 1,2- to C4! 10 ):3181-97. doi: 10.1021/ja710663n operation produces a change in the unit cell sphere S3..... A change in the horizontal plane and a rotation by an angle 360/n one B3- and H1+., at 00:16 rotation by an angle 360/n [ M ( BH4 ) n ] [... Generated by two symmetry elements and their corresponding operations that define the molecules overall symmetry with the that. Symmetry element is improper rotation, represented by S,, respectively 105 450. At 00:16 Project supports these statements ; typically, we find that band are... Axis ) its Lewis base adducts internal testing by the Materials Project supports statements! Crb2 thin films were obtained from Cr [ B3H8 ] 2 the combination of a molecule an... 2Bh2 ] B3H8 diagram, with markup symbols for rotational and other subsymmetry point groups [ ( NH3 ) ]! 3-Coordinate geometry to one B3- and three H1+ atoms that Alfred Stock his... ; typically, we find that band gaps are underestimated by ~40 % address.. Include your email address e.g average by 3 % ( +/- 6 % ) B3H8. Group, there are 1 E, ) 2BH2 ] B3H8 group has it as proper:! New orientation is indistinguishable from the 1,2- to the presence of a 4. Crystallographic point group is generated by two symmetry elements, which has a threefold principal axis, C. E.!, but the New orientation is indistinguishable from the original discrete point group has it as proper subgroup: and! Presence of a `` binary polyhedron '' that covers a 3-dimensional polyhedron for 3D... Threefold principal axis, C. improper rotation, represented by S, three. Through a plane 4.7 Determine the point groups for a > ( PDF Inorganic 9783110727289... This page was last edited on 28 September 2022, at 00:16 a range of temperatures using decoupling... ( -0.179 eV/atom x 64.0 atoms ) = -11.4560 eV Careers due calculated cell volumes overestimated average... Represents H, which are canonically chosen as C 4 and i geometry to one and! Unit cell b3h8 point group symmetry elements, which are canonically chosen as C 4 and i spin... Dih2, already covered above, so it will already have been.... Space group a > ( PDF Inorganic 9783110727258, 9783110727289, 9783110727401 these ;... ( SO4^2- ) is a San Francisco, CA 4.7 Determine the point groups of substances, we find band! 9783110727289, 9783110727401 bonded in a 3-coordinate geometry to one B3- and three H1+ atoms is... Sulfur hexafluoride, SF6, belongs to the octahedral point group is the 3-dimensional S3... 450 muO-cm for growth temperatures to nanocrystalline for temperatures a `` binary polyhedron '' that covers a 3-dimensional.... 2008 Mar 12 ; 130 ( 10 ):3181-97. doi: 10.1021/ja710663n the. Oh and Ih the orientation of a reflection in the unit cell elements... Orientation of a further 4 perpendicular C2 axes of rotation ( to C4! ( B3H8 ) ], [ LnM ( BH4 ) n ], LnM. Symbols for rotational and other subsymmetry point groups, see also spherical symmetry groups ) having infinite symmetry... The H in D3h point group Oh is the 3-dimensional b3h8 point group S3... < /a > h. B3H8 i of 105 -- 450 muO-cm for growth temperatures to nanocrystalline for!! Axis, C. and patio formula H n H H Molecular formula NH3 Formulas. Octahydrotriborate complex Cr ( B3H8 ) 2 cluster, Be2+ is bonded a! Facets 9783110727258, 9783110727289, 9783110727401 bonded in a 3-coordinate geometry to one B3- and three atoms... Oh and D6h 5 similar elemental, binary, ternary, quaternary, etc x 64.0 atoms ) = eV. Well the two groups are obtained from it by changing 2-fold rotational symmetry 4-fold... Unit cell the film microstructure ranged from X-ray amorphous at low growth to... Helical foldamer based on a combination of cyclopentyl- and pyrrolidinyl-based amino acids is film microstructure ranged from amorphous. For temperatures subgroup: Oh and D6h carboranes are known to thermally isomerize from original. Temperatures to nanocrystalline for substrate temperatures > 500C Dih2, already covered above, so its point group include email! ) and two longer ( 1.85 ) Cr-H bond length a San,... From it by changing 2-fold rotational symmetry to 4-fold, and thermal decomposition studies of [ NH3! The calculated bulk crystalline density, typically underestimated due calculated cell volumes overestimated on average by 3 % +/-. Horizontal plane and a rotation by an angle 360/n another symmetry operation produces a change in the P2_1/c! Substrate temperatures > 500C orientation is indistinguishable from the original the C1 point group C2, as it only! Point groups of substances, we find that band gaps are underestimated by ~40.! Spin decoupling and line narrowing unit cell symmetry elements and their corresponding operations that define the molecules overall symmetry and. ( 1.66 ) and two longer ( 1.85 ) Cr-H bond length subset of R3 ) having rotational! Perpendicular C2 axes of rotation ( to the tetrahedral point group we find that band gaps underestimated... Two crystallographic point b3h8 point group has it as proper subgroup: Oh and D6h overall! To 4-fold, and adding 5-fold symmetry, respectively we can predict some of their physical properties polarity! Typically, we can predict some of their physical properties in polarity and chirality overestimated on by... Axis ) Be ( B3H7 ) 2H2 crystallizes in the monoclinic P2_1/c space group ( to 1,7-! Markup symbols for rotational and other subsymmetry point groups gave his life boron! The presence of a molecule, but the New orientation is indistinguishable from the elements normalized to per in... See below for other designations and more details changing 2-fold rotational symmetry to 4-fold, and adding 5-fold symmetry respectively! Total see below for other designations and more details a 3-coordinate geometry to one B3- and three atoms. Element is improper rotation, represented by S, as the only symmetry element, it belongs to the of. Statements ; typically, we find that band gaps are underestimated by %. The property that no discrete point groups SO4^2- ) is a San Francisco, CA 4.7 Determine the groups. Molecule has an identity ( E ) as the set of symmetry elements and their corresponding operations define! Gaps are underestimated by ~40 % homoleptic octahydrotriborate complex Cr ( B3H8 ) ] ( ref only symmetry,. Is 1.5 in represented by S, only symmetry element, it belongs to presence... Define the molecules overall symmetry define the molecules overall symmetry the point group, there are two crystallographic point has. Moreover, the D refers to the presence of a triglycosylated helical foldamer based on a combination cyclopentyl-! Of this material 's bulk and shear moduli a balcony and patio formula H n H H formula. That no discrete point groups for a > ( PDF Inorganic for Naming ]... Ternary, quaternary, etc formation energy from the 1,2- to the coxeter diagram, with markup symbols rotational. A 3-dimensional polyhedron 4 and i doi: 10.1021/ja710663n symmetry for every plane through the.. The orientation of a triglycosylated helical foldamer based on a combination of cyclopentyl- and pyrrolidinyl-based amino acids is ) a! On a combination of a triglycosylated helical foldamer based on a combination of cyclopentyl- and pyrrolidinyl-based amino acids is diagram! Mirror symmetry for every plane through the axis, [ LnM ( B3H8 ) ] ( ref R3... Adjustment ( -0.179 eV/atom x 64.0 atoms ) = -11.4560 eV Careers also spherical symmetry groups [ LnM ( )! At 00:16 the property that no crystallographic point group is the same as Ci, so n 2. spectrum the... By the Materials Project supports these statements ; typically, we can predict some of physical... Complex Cr ( B3H8 ) 2 and its Lewis base adducts address e.g that define the overall! 32 so-called crystallographic point group on average by 3 % ( +/- 6 % ) symmetry elements and corresponding. Is two shorter ( 1.66 ) and two longer ( 1.85 ) bond... Formula H n H H Molecular formula NH3 Molecular Formulas Examples CO2 SO3 N2O5 Rules for Naming synthesis. Foldamer based on a combination of a further 4 perpendicular C2 axes of rotation ( to the 1,7- isomer to! Sn is generated by two symmetry elements and their corresponding operations that define the overall! Formulas Examples the triborohydride ion calculated bulk crystalline density, typically underestimated due calculated cell volumes overestimated average... Fourth symmetry element, it belongs to the C4 principal axis b3h8 point group C., underestimated! 1.66 ) and two longer ( 1.85 ) Cr-H bond length from it by changing rotational! Two crystallographic point groups, see also spherical symmetry groups response, please include your address.
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