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1Author    T. Platzner, J. K. ThomasRequires cookie*
 Title    Fluorescence and Proton Nuclear Magnetic Resonance Studies of Thallous Ions - Crown Ether Complexes in Organic Solvents  
 Abstract    The complexing of thallous ions (T1+), with the crown ether dibenzo 18 crown-6 poly-ether (DB) has been studied by NMR, fluorescence, and pulse radiolysis techniques. NMR data show a strong interaction of the T1+ ions with the aromatic moieties. This is also illustrated by a static quenching of the aromatic fluorescence by Tl + . The rates of reactions of T1+ with hydrated electrons eaq~ and pyrene excited singlet states are decreases on complexing the ion by the crown ether. 
  Reference    Z. Naturforsch. 33b, 614—618 (1978); received December 12 1977/March 13 1978 
  Published    1978 
  Keywords    Photochemistry, Fluorescence, Crown Ethers, Biology 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0614.pdf 
 Identifier    ZNB-1978-33b-0614 
 Volume    33 
2Author    Jürgen KeimRequires cookie*
 Title    Ein Beitrag zur Photochemie aromatischer Nitroverbindungen, III* A Contribution to the Photochemistry of Aromatic Nitro Compounds  
 Abstract    During UV irradiation of nitrobenzene and some derivatives in benzene solution biphenyls are formed as in the case of the corresponding iodobenzenes. Using fluorobenzene as a solvent, isomeric fluorobiphenyls (o, TO, p) will be found as reaction products having a definite distribution (o >m > p), which is characteristic for substitution by radicals. Therefore, we conclude that the CN-bond is split homolytically. Besides the biphenyls, other important reaction products of the aromatic nitro compounds -phenols and nitro-phenols -are identified. 
  Reference    Z. Naturforsch. 34b, 995—998 (1979); eingegangen am 28. Februar 1979 
  Published    1979 
  Keywords    Photochemistry, Aromatic Nitro Compounds, UV 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0995.pdf 
 Identifier    ZNB-1979-34b-0995 
 Volume    34 
3Author    H. Parlar+, Y. Inanici++Requires cookie*
 Title    Eine nicht erwartete intramolekulare Photoreaktion eines Hexachloroctahydrodimethanonaphthalins  
 Abstract    Photoreactions of 1,2,3,4,10,10-hexachloro-6,7-epoxy-l,4,4a,5,6,7,8,8a-octahydro-l,4-endo, endo-5,8-dimethano-naphthaline (1) were stud-ied in acetone with wavelengths above 290 nm. With the help of column chromatography an unusual isomerisation product (4) could be isolated, whose structure was established by spectral data obtained by mass spectrometry infrared spectroscopy, X H and 13 C nuclear magnetic resonance measurements. Hexachloroctahydrodimethanonaphthaline gehö-ren zu den bekanntesten Cyclodieninsektiziden, 
  Reference    (Z. Naturforsch. 36b, 125—126 [1981]; eingegangen am 12. August 1980) 
  Published    1981 
  Keywords    Photochemistry, Isomerisation Reactions, Hexachlorooctahydrodimethanonaphthalines 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0125_n.pdf 
 Identifier    ZNB-1981-36b-0125_n 
 Volume    36 
4Author    Arnd Vogler, Josef Kisslinger, WarrenR. RoperRequires cookie*
 Title    Photochemistry of Osmium-Carbyne Complexes  
 Abstract    Upon charge transfer (Os to carbyne) excitation the carbyne complexes Os(CPh)(CO)(PPh3)2Cl and [Os(CPh)(CO)2(PPh3)2] + with Ph = C6H5 are converted to the carbene complex Os(CHPh)(CO)(PPh3)2Cl2 in solutions containing HCl. It is suggested that the relaxed CT state can be described as square-pyramidal Os(II) complex containing a bent carbyne ligand which carries a lone pair at the coordinating carbon atom. Product formation occurs by the addition of a proton to the carbyne ligand and by attaching a chloride to the osmium completing an octahedral coordination. The cationic carbene complex thus formed is apparently not stable but undergoes a substitut ion of a CO ligand by chloride. 
  Reference    Z. Naturforsch. 38b, 1506—1509 (1983); received July 5 1983 
  Published    1983 
  Keywords    Photochemistry, Carbyne Complexes, Osmium Complexes 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-1506.pdf 
 Identifier    ZNB-1983-38b-1506 
 Volume    38 
5Author    Horst Kunkely, Amd VoglerRequires cookie*
 Title    Photoreactivity of Coordinated Phenylhydrazine. Intraligand Excitation of ReCl(CO)3(PhNH-NH2)2  
 Abstract    The complex of ReCl(CO)3(PhNH-NH2)2 shows an absorption band at A max = 272 nm which is assigned to an IL (intraligand) transition of the coordinated phenylhydrazine. Upon IL excitation the complex undergoes a decomposition with 4> = 0.03 at Ajrr = 280 nm. 
  Reference    Z. Naturforsch. 52b, 214—216 (1997); received September 20 1996 
  Published    1997 
  Keywords    Rhenium Complexes, Phenylhydrazine Complexes, Photochemistry 
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 TEI-XML for    default:Reihe_B/52/ZNB-1997-52b-0214.pdf 
 Identifier    ZNB-1997-52b-0214 
 Volume    52 
6Author    Arnd Vogler, Alfred KernRequires cookie*
 Title    Photoredox Reaction of Jrans-4-Stilbenecarboxylatopentaamminecobalt(III)  
 Abstract    The irradiation (A = 313nm) of aqueous [Co(III)(NH3)5TSC] 2 + (TSC -= transA-stilbenecarboxylate) leads to a redox reaction with formation of Co 2+ as has been shown previously. The TSC -ligand is oxidized to the radical in the primary photoreaction. At higher complex concentrations IO -2 M) this TSC radical is oxidized to stable products (0 = 0.09 ± 0.02) by [Co(NH3)5TSC] 2 +, which is reduced to Co 2 + leading to release of the TSC" ligand (0 = 0.07 ± 0.02). Co 2 + is thus formed by both the secondary and the primary photochemical reaction (ÖWraii = 0.16). At low complex concentrations (< 10 -4 M) in the presence of air, the primary TSC radical is scavenged by O2. Benz-aldehyde is an oxidation product. This reduces the formation of Co 2 + to 0 = 0.09 ± 0.02, which is taken to be the efficiency of the primary photochemical step. It is suggested that the photoredox reaction is initiated by an electron transfer from the first excited singlet of the TSC -ligand. As shown by sensitization experiments, the population of the lowest TSC -triplet leads to the usual trans/cis isomerization of the TSC -ligand, but not to the redox reaction. 
  Reference    Z. Naturforsch. 34b, 271—274 (1979); received November 13 1978 
  Published    1979 
  Keywords    Redox Reaction, Photochemistry, Cobalt(III) Complex, Stilbenecarboxylate 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0271.pdf 
 Identifier    ZNB-1979-34b-0271 
 Volume    34 
7Author    Peter BoehmRequires cookie*
 Title    R obert Schlögl and H anns  
 Abstract    Intercalation compounds of graphite with SnCl4 have been prepared by reaction in SOCl2/CCl4 or by UV irradiation in CC14 or 1,2-dichloroethane. Mix­ tures of 1st, 2nd, and 3rd stages have been obtained. Chemical analyses and 119Sn Mößbauer spectra indi­ cate that SnCle2^ ions are intercalated. Solvent molecules are co-intercalated. 
  Reference    (Z. Naturforsch. 39b, 112 [1984]; received August 12 1983) 
  Published    1984 
  Keywords    Graphite Intercalation Compounds, Hexachlorostannate, Photochemistry, Tin Tetrachloride 
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 TEI-XML for    default:Reihe_B/39/ZNB-1984-39b-0112_n.pdf 
 Identifier    ZNB-1984-39b-0112_n 
 Volume    39 
8Author    Wolfgang Gerhartz, Friedrich-Wilhelm Grevels, WernerE. Klotzbücher, ErnstA. Koerner Von Gustorf, RobinN. PerutzRequires cookie*
 Title    Low-Temperature Matrix Photochemistry of (f/ 4 -Diene)tetracarbonylchromium Complexes  
 Abstract    Photolysis of (^ 4 -diene)Cr(CO) 4 complexes (diene = butadiene, trans,trans-2,4-hexadiene, 2,3-dimethylbutadiene) in Ar, N 2 , and CO matrices at 10-12 K was monitored by infrared and UV-Vis spectroscopy. In argon and dinitrogen matrices loss of CO ist the predominant photoreaction. The resulting fac-(rf-diene)Cr(CO) 3 can take up N 2 from the matrix to form (?7 4 -diene)Cr(CO) 3 (N 2). In the case of the hexadiene complex this process requires matrix an-nealing subsequent to photolytic loss of CO. Photolysis in CO matrices, by contrast, results in stepwise displacement of the diene ligand, yielding (/7 2 -diene)Cr(CO) 5 and ultimately Cr(CO) 6 . 
  Reference    Z. Naturforsch. 40b, 518—523 (1985); received November 13 1984 
  Published    1985 
  Keywords    Matrix Isolation, Photochemistry, Carbonylchromium Diene Complexes, IR Spectra 
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 TEI-XML for    default:Reihe_B/40/ZNB-1985-40b-0518.pdf 
 Identifier    ZNB-1985-40b-0518 
 Volume    40 
9Author    Karin Oldenburg, Arnd VoglerRequires cookie*
 Title    Electronic Spectra and Photochemistry of Tin(II), Lead(II), Antimony(III), and Bismuth(III) Bromide Complexes in Solution  
 Abstract    The electronic spectra o f brom o complexes o f main group metal ions with an s2 electronic configuration (SnBr3~, PbBr3~, PbBr42_, SbBr4~, SbBr63~, BiBr4~, BiBr63~) in acetonitrile show long-wavelength absorption bands which are assigned to metal-centered sp transitions. C om ­ pared to the corresponding chloro complexes the sp bands o f the bromo complexes appear at longer wavelength due to sp/LM C T mixing (LM CT = ligand-to-metal charge transfer). As a result o f this mixing the luminescence which originates from low-energy sp excited states is much weaker than that o f the chloro complexes. M oreover, some o f the bromo complexes (e.g. BiBr4~) undergo a photochemical redox decom position induced by LMCT excitation. 
  Reference    Z. Naturforsch. 48b, 1519—1523 (1993); received July 1 1993 
  Published    1993 
  Keywords    Electronic Spectra, Bromo Complexes, Main Group M etals, Photochemistry 
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 TEI-XML for    default:Reihe_B/48/ZNB-1993-48b-1519.pdf 
 Identifier    ZNB-1993-48b-1519 
 Volume    48 
10Author    Horst Kunkely, AmD. VoglerRequires cookie*
 Title    Photoreactivity of Titanocene Pentasulfide  
 Abstract    The electronic spectrum o f Cp2TiSs shows a long-wavelength absorption at Am ax = 492 nm which is assigned to the lowest-energy S52~ ^ T i IV ligand-to-metal charge transfer (L M C T) transition. The photolysis o f the complex in C H 2CI2 leads to the formation o f Cp2T iC l2 and elemental sulfur. It is suggested that L M C T excitation initiates a reductive elimination with the extrusion o f S5 while the reduced titanocene is reoxidized by the solvent. 
  Reference    Z. Naturforsch. 53b, 224—226 (1998); received December 12 1997 
  Published    1998 
  Keywords    Charge Transfer, Titanium Complexes, Sulfide Complexes, Photochemistry 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0224.pdf 
 Identifier    ZNB-1998-53b-0224 
 Volume    53 
11Author    Horst Kunkely, Arad VoglerRequires cookie*
 Title    Photooxidation of Dicyanoaurate(I) Induced by Metal-to-Ligand Charge Transfer Excitation  
 Abstract    The irradiation of [Au(CN)2]_ in oxygen-saturated acetonitrile leads to photooxidation of Au(I). In the presence of additional chloride [AutCN^CL]-is formed with < /> = 0 .5 x 1 0 -4 at Ajrr = 2 5 4 nm. It is assumed that [Au(CN)2]~ in its metal-to-ligand charge transfer state undergoes an excited state electron transfer to oxygen in the primary photochemical step. 
  Reference    Z. Naturforsch. 53b, 853—855 (1998); received April 12 1998 
  Published    1998 
  Keywords    Photochemistry, Charge Transfer, Gold Complexes, Cyanide Complexes 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0853.pdf 
 Identifier    ZNB-1998-53b-0853 
 Volume    53 
12Author    Horst Kunkely, Arnd VoglerRequires cookie*
 Title    Photochemical Reductive Elimination of Nitrogen from Triazidogallium(III). Generation of Luminescent Gallium(I)  
 Abstract    The irradiation of Ga(N3)3 in CH3CN leads to a reductive elimination of nitrogen according to the equation Gam(N3)3 —► Ga*N3 + 3N2 (0 = 0.002 at Ain = 254 nm). Ga+ in CH3CN is characterized by its absorption (Amax = 298 nm) and emission (Amax = 475 nm) spectrum. 
  Reference    Z. Naturforsch. 53b, 1180—1182 (1998); received July 9 1998 
  Published    1998 
  Keywords    Photochemistry, Charge Transfer, Gallium Complexes, Azide Complexes 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-1180.pdf 
 Identifier    ZNB-1998-53b-1180 
 Volume    53 
13Author    HeinzM. AuserRequires cookie*
 Title    Der Ablauf komplizierter Photoreaktionen in zähen Medien The Evolution of Complicated Photoreactions in Viscous Media  
 Abstract    The calculation o f the photochemical yield of simple reactions in viscous media was discussed earlier in a rather formal way. In this paper the basic equation will be derived in a more convenient way and the numeric results of an application to photoisomerization are given. The main purpose is to demonstrate the possibility to handle even complicated reactions. 
  Reference    Z. Naturforsch. 34c, 1264—1268 (1979); received August 13 1979 
  Published    1979 
  Keywords    Kinetics, Photochemistry, Viscous Media, Complicated Reactions 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-1264.pdf 
 Identifier    ZNC-1979-34c-1264 
 Volume    34 
14Author    Marion Lindemami, Reinhard Benn, Richard Goddard, Carl KrügerRequires cookie*
 Title    Friedrich-Wilhelm Grevels  
 Abstract    Extended photolysis of M(CO)ö (M = W, Mo) and methyl acrylate or dimethyl fumarate results in formation of (^ 2 -olefin)2M(CO)4 via the less stable (^ 2 -olefin)M(CO)5 complexes. X-ray structure analysis of (^-methyl acrylate)2W(CO)4 reveals the trans-staggered arrangement of the olefinic ligands. Rotational barriers are determined by variable temperature NMR spectroscopy. 
  Reference    Z. Naturforsch. 35b, 1298—1309 (1980); eingegangen am 2. Mai 1980 
  Published    1980 
  Keywords    Carbonyltungsten Olefin Complexes, Photochemistry, NMR Spectra, Fluxional Behaviour, X-ray 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-1298.pdf 
 Identifier    ZNB-1980-35b-1298 
 Volume    35 
15Author    George Sosnovsky, GaryA. KarasRequires cookie*
 Title    Reactions of J-Butyl Peresters, XVII The Photochemical Reaction of Dialkyl t-Butylperoxy Phosphates and Alkyl f-Butylperoxy Alkylphosphonates with Cyclohexene and Cyclopentene in the Presence of Copper Ions  
 Abstract    The photochemical reaction of dialkyl f-butylperoxy phosphates (1) and alkyl *-butyl-peroxy alkylphosphonates (2) with cyclohexene in benzene in the presence RCk (R0)2P(0)00C(CH3)3 ^PIOIOOCICH^ 
  Reference    Z. Naturforsch. 33b, 1177—1183 (1978); received June 20 1978 
  Published    1978 
  Keywords    i-Butylperoxy Phosphates, £-Butylperoxy Phosphonates, Copper Ion Catalysis, Triplet Sensitizers, Photochemistry 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-1177.pdf 
 Identifier    ZNB-1978-33b-1177 
 Volume    33 
16Author    Friedrich-Wilhelm Grevels, Konrad Schneider, Carl Krüger, Richard GoddardRequires cookie*
 Title    Tricarbonyl(^ 4 -1.5-cümethylen-2.6-cümethylcyclooctan)eisen: photochemische Synthese und Struktur Tricarbonyl(^ 4 -l,5-dimethylene-2,6-dimethylcyclooctane)iron: Photochemical Synthesis and Structure  
 Abstract    Extended photolysis of pentacarbonyliron in neat 2,3-dimethylbutadiene results in dimerization of the diene and formation of tricarbonyl(?y 4 -l,5-dimethylene-2,6-dimethyl-cyclooctane)iron (1). The structure of complex 1 is characterized by a trigonal-bipyramidal geometry whereby the exocyclic double bonds of the diene ligand and one of the carbonyl groups lie exactly in the equatorial coordination plane. 
  Reference    Z. Naturforsch. 35b, 360—365 (1980); eingegangen am 5. November 1979 
  Published    1980 
  Keywords    Carbonyliron Olefin Complexes, Dimerization of Dimethylbutadiene, Photochemistry, NMR, X-ray 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-0360.pdf 
 Identifier    ZNB-1980-35b-0360 
 Volume    35 
17Author    HeinzG 0 Becker, Dietmar Pfeifer, Reiner RadegliaRequires cookie*
 Title    Democratic Republic  
 Abstract    13 C and 15 N photo-CIDNP effects were determined for the reversible electron transfer from pyrene to arene diazonium salts on excitation of the charge transfer band at 360 nm. The diazonium salts being the products of back electron transfer ("cage products") show enhanced absorption for 13 C(1) and the 15 N-enriched diazonium group, whereas the escape products, ArH or lö N2, respectively, yield emission signals. It was shown that the inten-sities of the CIDNP effects depend on the rates of intersystem crossing kjSC within the geminate radical pair, i.e. on the magnetic nucleus used as a probe of the CIDNP effect. Using iH, 13 C or 15 N the time domain of observation can be manipulated in the ranges of 90-100 ns, 15-20 ns and 3-5 ns, respectively. Furthermore, the CIDNP intensities depend on the proper balance of the rate of electron back transfer, k_e, and the rate kp of formation of the escape product. Since k_e increases with increasing energy of the geminate radical pair, this balance and therefore the CIDNP intensities vary according to the substituent present and the electron donor used. 
  Reference    Z. Naturforsch. 38b, 1591—1597 (1983); received April 6 1983 
  Published    1983 
  Keywords    Photochemistry, Dediazoniation, Electron Transfer, Chemical Induced Nuclear Polarization (CIDNP), Arene Diazonium Salts 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-1591.pdf 
 Identifier    ZNB-1983-38b-1591 
 Volume    38