The crystal structures of two phenolic Mannich bases. 1-[(2.3,4.5-tetrachloro-6-hydroxy)phenyl]-N,N-dimethylmethanamine (1) and 1-[(3-nitro-6-hydroxy)phenyl]-N. N-diisobutylmethanamine (2), were determined by using the single crystal X-ray diffraction method.The results and conditions for molecule 1. C9H9NOCl4, are: M(r) = 288.99, monoclinic, C2/c, a = 21.88(2) angstrom, b = 8.419(7) angstrom, c = 14.63(1) angstrom, beta = 119.62(4)-degrees, V = 2344(3) angstrom3, Z = 8. D(calc) = 1.638 g cm-3, lambda(MoKalpha) = 0.71069 angstrom, mu = 9.87 cm-1, F(000) = 1168, T = 296 K, R = 0.043 for 1559 observed reflections.For molecule 2, C15H24N2O3, results and conditions are: M(r) = 280.37, orthorhombic, P2(1)2(1)2(1), a = 8.850(7) angstrom, b = 29.399(6) angstrom, c = 6.22(1) angstrom, V = 1620(4) angstrom3, Z = 4, D(calc) = 1.150 g CM-3, lambda(MoKalpha) = 0.71069 angstrom, mu = 0.75 cm-1, F(000) = 608, T 296 K, R 0.062 for 755 observed reflections.Compound 1 was determined to have intermolecular hydrogen bonding involving the zwitterionic form N+-H...O-. For compound 2 intramolecular H-bonding was observed with the N ... H 0 form retained. Complementary IR measurements in the solid state were in good agreement with the X-ray results.The geometry of the hydrogen bond present depends on the substituents at the amine nitrogen atom.

EXAFS data, collected at the SRS at Daresbury Laboratory, for aqueous solutions of MnBr2 and MnCl2 at a variety of concentrations were analysed by least-squares curve fitting calculations. The data, obtained at ambient temperature, were found to be consistent with equilibria between species of the type (MnX(6-n)(H2O)n)(n-4)+ (where X=Cl, Br and n=4, 5, 6) for which it was possible to determine the average value of n (i.e. nav) at each concentration. To fit the data, a third distance, in addition to Mn-X and Mn-O in the complexes, was shown to be significant in the least-squares calculations; this third distance at 4.4 AA represents the radius of the first hydration sphere around the complexes and is reasonably interpreted as Mn to solvent water molecules hydrogen bonded to the water molecules in the complexes. By carefully parameterising the calculations using EXAFS data for solid reference compounds, the dependence of nav on concentration was determined; calculations were carried out both with data sets for single concentrations and also with data sets for four different concentrations simultaneously.

Ab initio SCF molecular orbital calculations have been performed on the free Cu(OH2)62+ complex in D2h symmetry. Two extrema in the adiabatic electron energy potential surface were obtained corresponding to a tetragonal distortion from the regular Th symmetry of the octahedral complex, as expected from the Jahn-Teller theorem in a case with strong E-e type vibronic coupling. The tetragonally elongated octahedral structure with Cu-20ax at 2.25 AA and Cu-40eq at 2.06 AA gave a slightly lower energy (72 cm-1) than the compressed geometry with Cu-20ax at 2.02 AA and Cu-40eq at 2.17 AA. The calculated Jahn-Teller energy is 650 cm-1 from that of the regular Th symmetry with Cu-60 at 2.115 AA. EXAFS measurements were performed on aqueous Cu2+ solutions and showed a greater distortion with Cu-40eq at 1.99 AA and Cu-20ax at about 2.29 AA. Infrared absorption spectroscopic measurements were made on the O-D stretching vibrations of HDO molecules in aqueous Cu2+ and Ni2+ solutions with added D2O in order to study the hydrogen bonds from the hydrated ions. A distorted Cu(OH2)62+ ion is expected to form hydrogen bonds of unequal strength because of the stronger polarisation of the more strongly bonded equatorial water molecules. Two bands ascribed to the hydration of the Cu2+ ion were obtained, the more intense corresponding to the strongest hydrogen bonds at approximately=2400 cm-1, and the weaker at approximately=2530 cm-1, whereas for Ni2+ only one band at approximately=2420 cm-1 was found. With the use of a correlation between RO...O versus nu OD from crystal structure data the mean hydrogen-bonded O...O distances to the second hydration shell are estimated to about 2.74 AA from the equatorial water molecules and 2.88 AA from the axial. The IR data show that the distortions induced by the Jahn-Teller effect on the second hydration sphere are visible on a vibrational timescale, despite the fast intramolecular inversion of the distortion axis between the three principal octahedral directions. The splitting of the nu OD bands in the Tutton salts Cs2(M(OH2)6)(SO4)2, M=Cu or Ni, with some added D2O has also been measured and compared to crystal structure data of the hydrogen bonded distances. The separation of about 107 cm-1 between the two groups of O-D stretching vibrations found in the Cu salt can be ascribed to a static Jahn-Teller effect.

Chemischer InformationsdienstVolume 13, Issue 49 Physical Organic Chemistry ChemInform Abstract: A GAS-PHASE ELECTRON DIFFRACTION STUDY OF THE MOLECULAR STRUCTURE OF THE STERICALLY STRAINED MOLECULE TRIS(TRIMETHYLSILYL)METHANE B. BEAGLEY, B. BEAGLEYSearch for more papers by this authorR. G. PRITCHARD, R. G. PRITCHARDSearch for more papers by this author B. BEAGLEY, B. BEAGLEYSearch for more papers by this authorR. G. PRITCHARD, R. G. PRITCHARDSearch for more papers by this author First published: December 7, 1982 https://doi.org/10.1002/chin.198249067AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume13, Issue49December 7, 1982 RelatedInformation

Chemischer InformationsdienstVolume 11, Issue 44 Physical Organic Chemistry ChemInform Abstract: A GAS-PHASE ELECTRON DIFFRACTION STUDY OF THE MOLECULAR STRUCTURE OF 1,1,1,2-TETRAFLUOROETHANE G. N. D. AL-AJDAH, G. N. D. AL-AJDAHSearch for more papers by this authorB. BEAGLEY, B. BEAGLEYSearch for more papers by this authorM. O. JONES, M. O. JONESSearch for more papers by this author G. N. D. AL-AJDAH, G. N. D. AL-AJDAHSearch for more papers by this authorB. BEAGLEY, B. BEAGLEYSearch for more papers by this authorM. O. JONES, M. O. JONESSearch for more papers by this author First published: November 4, 1980 https://doi.org/10.1002/chin.198044087AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References G. N. D. AL-AJDAH, B. BEAGLEY, M. O. JONES, A GAS-PHASE ELECTRON DIFFRACTION STUDY OF THE MOLECULAR STRUCTURE OF 1,1,1,2-TETRAFLUOROETHANE, J. Mol. Struct., 1980, 65, 271. DOI: 10.1016/0022-2860(80)85200-8; 10.1016/0022-2860(80)85200-8 CASWeb of Science®Google Scholar Volume11, Issue44November 4, 1980 ReferencesRelatedInformation

AbstractZur Deutung der Ergebnisse einer Fourier‐Synthese für einen zu 30% ausgetauschten NaFeX‐Zeolithen werden 3 alternative Modelle entwickelt.

The molecular structures of germyl isocyanate and digermylcarbodi-imide in the gas phase have been determined by electron diffraction. Both appear to have non-linear heavy atom skeletons, with GeNC angles of 141.3(3) and 138.0(5)°. Principal bond lengths (ra) are: for GeH3NCO, (Ge—N), 183.1(4); (NC), 119.0(7); (CO) 118.2(7) pm: for GeH3N̄CNGeH3, (Ge—N), 181.3(5); (NC) 118.4(9) pm. The structures are discussed in terms of valence bond models, (p→ d)π-bonding, and “hard-sphere” radii of germanium and carbon.

Three alternative models are proposed to explain the map obtained from a difference Fourier synthesis for a NaFeX zeolite (30% exchanged). The models are based on the extent of distortion of the zeolitic structure which arises when sodium ions are replaced by ferric ions.

Chemischer InformationsdienstVolume 4, Issue 47 Organoelement Compounds ChemInform Abstract: THE MOLECULAR STRUCTURE OF TRIMETHYL BISMUTH, BY GAS-PHASE ELECTRON DIFFRACTION B. BEAGLEY, B. BEAGLEYSearch for more papers by this authorK. T. MCALOON, K. T. MCALOONSearch for more papers by this author B. BEAGLEY, B. BEAGLEYSearch for more papers by this authorK. T. MCALOON, K. T. MCALOONSearch for more papers by this author First published: November 20, 1973 https://doi.org/10.1002/chin.197347392AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume4, Issue47November 20, 1973 RelatedInformation

The use of Cox and Bonham scattering factors for tin in electron-diffraction studies of a number of tin compounds leads to anomalously low amplitudes of vibration. The anomaly is due to overdamping of the calculated molecular intensities by the phase-angle dependent terms cos(ηiηj). Modified scattering factor calculations eliminate the anomaly.

The molecular structures of dimethylaminodifluorophosphine, Me2NPF2, and aminodifluorophosphine, H2NPF2, in the gas phase have been determined by the sector-microphotometer method of electron diffraction. The principal parameters for dimethylaminodifluorophosphine are: r(P–F) 1·589 ± 0·003, r(P–N) 1·684 ± 0·008, r(C–N) 1·448 ± 0·006 Å; P–N–C 118·3 ± 0·6°, and C–N–C 111·8 ± 1·5°; for aminodifluorophosphine r(P–F) 1·581 ± 0·003, and r(P–N) 1·661 ± 0·007 Å. The positions of the hydrogen atoms are not well defined, but the angles at nitrogen are probably close to those at nitrogen in the dimethyl compound. Both molecules adopt a staggered conformation.

Chemischer Informationsdienst. Organische ChemieVolume 2, Issue 24 Organoelement Compounds ChemInform Abstract: BESTIMMUNG DER MOLEKULARSTRUKTUR VON DIMETHYLAMINODIFLUORPHOSPHIN UND AMINODIFLUORPHOSPHIN IN DER GASPHASE DURCH ELEKTRONENBEUGUNG G. C. HOLYWELL, G. C. HOLYWELLSearch for more papers by this authorD. W. H. RANKIN, D. W. H. RANKINSearch for more papers by this authorB. BEAGLEY, B. BEAGLEYSearch for more papers by this authorJ. M. FREEMAN, J. M. FREEMANSearch for more papers by this author G. C. HOLYWELL, G. C. HOLYWELLSearch for more papers by this authorD. W. H. RANKIN, D. W. H. RANKINSearch for more papers by this authorB. BEAGLEY, B. BEAGLEYSearch for more papers by this authorJ. M. FREEMAN, J. M. FREEMANSearch for more papers by this author First published: June 15, 1971 https://doi.org/10.1002/chin.197124013AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume2, Issue24June 15, 1971 RelatedInformation

The molecular structure of (CH3)2S2 has been studied by gas-phase electron diffraction. The results confirm a published microwave study, but are superior in precision. The orientation of the methyl groups was refined and it is established that the C—H bonds are staggered (or nearly so) with respect to the S—S bond. The principal parameters are C—H = 1.090±0.007 Å, S—C = 1.806±0.002 Å, S—S = 2.022±0.003 Å, ∠SSC = 104.1±0.3°; the dihedral angle of the CSSC skeleton is 83.9±0.9°. The S—S length is significantly shorter than found in H2S2. The work differs from a standard structure analysis in that two sets of data were used, based on different treatments of the background. Slight differences in some of the less well determined parameters were observed.

A careful re-determination of the molecular structure of trisilylamine in the gas phase has been carried out by electron diffraction. The main molecular parameters obtained are : Si—N = 1.734±0.002 Å, ∠SiNSi = 119.7±0.1°. The apparent slight deviation from planarity is associated with a shrinkage effect. The results are compared with those for related molecules possessing Si—N bonds.

The molecular structure of methyl silyl ether CH3OSiH3, has been deter- mined in the gas phase by the sector microphotometer method of electron, diffrac- tion. The Si-O bond length is 1.640±0.003 Å, the C-O bond length is 1.418±0.009 Å, and the Si-O-C angle is 120.6±0.9°.

The molecular parameters of digermane have been determined by gas-phase electron diffraction. The bond lengths (rg(1) values) are Ge—H = 1.541±0.006 Å, Ge—Ge = 2.403±0.003 Å, and ∠HGeH = 106.4±0.8°. The Ge—Ge length is 0.046 Å shorter than the value found in solid germanium.

The molecular structure of phenyl silyl ether C6H5OSiH3 has been studied by the sector-microphotometer method of electron diffraction. The Si—O bond length is 1.648 ± 0.007 Å, the C—O bond length is 1.357 ± 0.009 Å, the Si—O—C angle is 121 ± 1° and the dihedral angle between the Si—O—C plane and the aromatic ring is 68 ± 3°. These results are discussed and compared with those for similar molecules.

The molecular structure of S2Cl2 has been determined accurately by electron diffraction. The ClSSCl chain configuration has the dimensions: S—Cl = 2.057 ± 0.002 Å, S—S = 1.931 ± 0.005 Å, SSCl = 108.2 ± 0.3°, ϕ(the dihedral angle between the two SSCl planes)= 84.8 ± 1.3°. The two bond distances occur within a single peak of the radial distribution curve; the resulting correlation problem was solved by carrying out refinements with constrained amplitudes. The study confirms the absence of the pyramidal isomer S = SCl2, but the existence of SClClS cannot be ruled out entirely from the electron diffraction results alone. The structure of S2Cl2 is compared with that of S2F2 where the S = SF2 isomer predominates.