Analytische Multielement-Anreicherung an metallhydroxidbeladener Cellulose

Zusammenfassung Es wird die analytische Multielement-Anreicherung an metallhydroxydbeladener Cellulose beschrieben. Metallhydroxide [z.B. Fe(OH)₃, In(OH)₃] in geringen Mengen auf einem anderen Spurenfänger (z. B. Cellulose) fixiert, zeigen ein hohes Sorptionsvermögen für Elementspuren [z. B. Al, As, Be, Bi, Cd, Co, Cr(III), Cu, Lanthanoide, Mn, Mo, Ni, Pb, Sn, Ti, V, Zn] im ng/l- bis g/ l-Bereich. Die Spuren-VerteilungskoeffizientenK _d an dem synergistisch wirkenden Mischkollektor [Cellulose/1% Fe(III) bzw. Cellulose/2% In(III)] erreichen auch in konzentrierten Salzlösungen Werte von 10⁴ bis 10⁵. Komplexierende Wasserinhaltsstoffe (z.B. Citrat, Huminsäure, Phosphat) stören die Spurenanreicherung kaum, abgesehen von starken Chelatbildnern (z.B. NTA). Hauptvorteile gegenüber der herkömmlichen Mitfällung an Metallhydroxiden sind eine vereinfachte Handhabung (Schüttelverfahren) sowie erheblich verringerte Kollektormengen [z. B. einige hundert Mikrogramm Fe(III), In(III)]. Nach Elution mit 2 M HCl werden die angereicherten Elementspuren durch Flammen-AAS (Injektionsverfahren) bzw. ICP-AES bestimmt. Die Nachweisgrenzen (3) der wasseranalytischen Verbundverfahren liegen vielfach bei 0,1 g/l, die relativen Standardabweichungens _r bei 0,03 bis 0,05.

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Analytical multielement preconcentration on metal hydroxide-coated cellulose

Summary The analytical preconcentration of trace metals on metal hydroxide-coated cellulose is characterized. Metal hydroxides [e.g., Fe(OH)₃, In(OH)₃], in small amounts fixed on another adsorbent (e.g., cellulose), strongly bind many trace metals [e.g., Al, As, Be, Bi, Cd, Co, Cr(III), Cu, lanthanoids, Mn, Mo, Ni, Pb, Sn, Ti, V, Zn] in the ng/l to g/l range. The sorption of trace metals on the synergistically acting collector [e.g., cellulose/1% Fe(III), cellulose/2% In(III)] proceeds with half times of some minutes. Furthermore, the element distribution coefficientsK _d between adsorbent and strong saline solutions are of the order 10⁴ to 10⁵. Dissolved complexing matters (e.g., citrate, humic acid, phosphate) with the exception of chelating agents (e.g., NTA) do not interfere. The main advantages compared with the conventional co-precipitation of trace metals with metal hydroxides, are a simplified procedure (batch method) and lowered metal amounts [e.g., some 100 g Fe(III), In(III)]. After elution (2 M HCl) the preconcentrated trace metals are determined by flame-AAS (injection technique) and ICP-AES. With the analytical procedure developed for water analysis, detection limits (3) of 0.1 g/l and relative standard deviations of 0.03 to 0.05 can be achieved for many elements in surface-, mineral- and sea-water.

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Teilweise vorgestellt auf der Jahrestagung 1984 der Fachgruppe Wasserchemie der GDCh, Bad Homburg v. d. H., 28.–30. 5.1984     

Semiquantitative estimation of the mycotoxins citrinin, Ochratoxin A, Aflatoxin M1 and penicillic acid on thin-layer chromatograms with a grey scale

Summary Spots of citrinin, ochratoxin A, aflatoxin M₁ and penicillic acid on thin-layer chromatograms can be semi-quantitatively estimated by using a grey scale, commonly used in photo laboratories. The detection limits are 0.01 g for citrinin, 0.006 g for ochratoxin A, 0.002 g for aflatoxin M₁ and 0.01 g for penicillic acid. Standard curves for these mycotoxins are given.

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Halbquantitative Bestimmung der Mycotoxine Citrinin, Ochratoxin A, Aflatoxin M₁ und Penicillinsäure auf Dünnschicht-Chromatogrammen mit Hilfe eines Graukeils

Zusammenfassung Mit Hilfe eines in Photolabors gebräuchlichen Graukeils können dünnschicht-chromatographische Flecke der obengenannten Mycotoxine halbquantitativ bestimmt werden. Die Nachweisgrenzen betragen 0,01 g für Citrinin, 0,006 g für Ochratoxin A, 0,002 g für Aflatoxin M₁ und 0,01 g für Penicillinsäure. Eichkurven werden angegeben.

     

Determination of Cd, Co, Cr, Cu, Fe, Mn, Ni and Pb in natural waters, alkali and alkaline earth salts by electrothermal atomic absorption spectrometry after preconcentration by column solid phase extraction

Methods are described for the determination of trace and ultra trace amounts of Cd, Co, Cr, Cu, Fe, Mn, Ni and Pb in natural waters, alkali and alkaline earth salts. Separation and preconcentration of trace metals is achieved by a column solid phase extraction procedure using silica gel modified with derivatives of dithiocarbamates — Na-DDTC (sodium diethyldithio-carbamate and HMDTC (ammonium hexamethylene-dithiocarbamate) as column packing material. The influence of the sorbent preparation procedure on the degree of sorption of the trace analytes is examined for different pH values of the sample solution. Isobutylmethyl ketone (IBMK) is proposed as an effective eluent for quantitative elution of retained metal ions. Optimal instrumental parameters for ETAAS determination of preconcentrated elements in organic eluate are presented. Practical application of sorbents in analysis of natural waters and alkali and alkaline earth salts is demonstrated. Proposed preconcentration procedure combined with ETAAS determination of trace analytes allows the determination of 0.04 g l^–1 Cd, 0.1 g l^–1 Cr, Cu, and Mn and 0.3 g l^–1 Co, Fe, Ni and Pb in natural waters and 1.10^–7% Cd, 3.10^–7% Cr and Mn, 7.10^–7% Co, Ni and Pb and 2.10^–6% Cu and Fe in alkali and alkaline earth salts.     

Solid phase extraction for sample preparation in trace analysis of ionogenic compounds by capillary isotachophoresis

Various sorbents recommended for solid phase extraction (SPE) in sample preparation procedures were studied for use in combination with capillary isotachophoresis (ITP). They were very efficient in achieving trace concentration levels (low ppb, i.e., low parts per 10⁹) for different types of ITP analytes present in environmental and biological matrices. A macroporous carbon sorbent was convenient for sample preparation in ITP analysis of short chain fatty acids (C₄–C₉) in drinking water. Chelating sorbents based on hydroxyalkyl methacrylate matrix with salicylate, thioglycolate and 8-hydroxyquinolinate functionalities were found to be very suitable for preconcentration of heavy metals with an inherent sample clean-up. An octadecyl-bonded silica sorbent enabled in ITP a photometric detection of -aminobutyrate (labeled with a 2,4,6-trinitrophenyl group) at concentrations considerably lower than required for the determination of this amino acid in cerebrospinal fluid (5·10^–8 mol/l).     

Preparation of L-asparagine complex of technetium-99m

Attempts have been made to employ magnesium oxide as the preconcentration agent for determination of trace metal sin seawater by neutron activation analysis. Hydrous magnesium oxide can efficienthy adsorb most cationic transition metals and rare earths in a simple water system. The adsorption behavior is believed to depend mainly from the association of the cationic species of the metals with MgO ₂ ^2– adsorbent. In seawater matrix some of the metal ions such as Hg²⁺, Ni²⁺, etc. may become inefficiently adsorbed owing to the formation of highly stable metal-chloro complexes with chloride ion. Usually the adsorption efficiencies of the metals can be recovered to be as high as the case in the simple water system if an acidified seawater (to pH1) is subjected to the adsorption experiment. In practice, a large volume of seawater (5 1) is stirred with a small amount of hydrous MgO (1 g). Thereafter, the trace metals adsorbed MgO is separated and taken to be neutron activated. The abundant sodium ion and ubiquitous bromide ion can be obviated by the adsorption process, thereby beneficial to the -spectrometry of the metals enriched on MgO.     

Crystal structure of Ag2TeS3 and Na(Na1−x Ag x )TeS3 (x≈0.5) and the geometry of Te(IV)S3 polyhedra

Summary Structural data determined by single crystal X-ray experiments (T=300 K) are reported for Ag₂TeS₃ (monoclinic, Cc-C _s ⁴ ;a=6.783(1),b=11.567(2),c=7.693(1) Å; =114.44(1)°;Z=4;R=0.044) and for Na(Na_1–x Ag _x )TeS₃ x0.5; monoclinic, P2₁/c-C _2h ⁵ ;a=5.761(9),b=12.171(8),c=8.342(4) Å; =92.26(6)°;Z=4;R=0.030). In both compounds the atomic arrangements are characterized by isolated trigonal pyramidal TeS₃ polyhedra, irregularly coordinated Ag and Na atoms forming AgS₄ and (Na, Ag)S₄ polyhedra, and slightly distorted NaS₆ octahedra. Crystals of both compounds were synthesized under moderate hydrothermal conditions from an equimolar mixture of the elements in concentrated aqueous ammonia and 5N NaOH solution, respectively.

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Kristallstruktur von Ag₂TeS₃ und Na(Na_1–x Ag _x )TeS₃ (x0.5) nebst einem Vergleich der Geometrie von TeS₃-Gruppen

Zusammenfassung Es wird über die mittels Röntgenbeugungsexperimenten an Einkristallen bei 300 K bestimmten Strukturen von Ag₂TeS₃ (monoklin Cc-C _s ⁴ ;a=6.783(1),b=11.567(2),c=7.693(1) Å; =114.44(1)°;Z=4;R=0.044) und Na(Na_1–x Ag _x )TeS₃ (x0.5; monoklin, P2₁/c-C _2h ⁵ ;a=5.761(9),b=12.171(8),c=8.342(4)Å; =92.26(6)°;Z=4;R=0.030) berichtet. In beiden Verbindungen ist die Atomanordnung durch isolierte trigonal-pyramidale TeS₃-Polyeder, unregelmäßig koordinierte Ag- und Na-Atome, AgS₄- und (Na, Ag)S₄-Polyeder bildend, sowie leicht verzerrte NaS₆-Oktaeder charakterisiert. Kristalle der beiden Verbindungen wurden unter moderaten Hydrothermalbedingungen aus einem equimolaren Gemenge der Elemente und konzentrierter wäßriger Ammoniaklösung bzw. 5N NaOH-Lösung gezüchtet.

     

Determination of trace elements in seawater by electrothermal atomic absorption spectrometry with and without a preconcentration step

The determination of the trace metals Cd, Pb and Cu in seawater by electrothermal atomic absorption spectrometry (ETA-AAS) has been investigated. A combination of the platform with mixed palladium nitrate-magnesium nitrate as matrix modifier and Zeeman background correction allows Cd an Pb to be determined by aqueous standard calibration in appropriately diluted seawater samples. Copper can be determined in undiluted seawater samples without chemical modification using a standard additions method. Detection limits (3) of 2.97,5.27 and 1.1 gl^–1 are obtained for Cd, Pb and Cu respectively. A Kelex-100 impregnated silica C18 material (Kelex 100-C18) has been tried and has proved to be effective as a column packing for extraction/preconcentration of these metals from seawater. Using the column extraction method, the sensitivity of the graphite furnace technique is enhanced 50-fold using a 10 l injection volume. Thus, the determination of the studied three metals in seawater at the ng.l^–1 level could be achieved.     

A combination of ring-oven and circular chromatography for trace metal analysis

Summary A chromatographic method for metal chelates of pyridine-2-aldehyde-2-quinolylhydrazone (PA QH) has been adapted to the ring-oven technique Advantage has been taken of the large difference inR _f -values of the cobalt, copper, nickel and iron(III) chelates on alumina, the acid stability of the cobalt PA QH complex, selective formation of chloride complexes of these metals and the use of specific spray reagents for copper and iron, such as rubeanic acid and KSCN to develop a simple and rapid field method for trace metal analysis. Quantitative estimation of these four metals with an accuracy ranging from 5.0 to 12% has been carried out in less than 30 minutes. Detection limits were found to be about 0.010g for nickel, 0.008g for copper and iron and 0.005g for cobalt. Other ions did not interfere in up to 10-fold excess. The suitability of this method for field work was tested by monitoring trace metals in fresh and sea water supplies and in algae.

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Zusammenfassung Ein chromatographisches Verfahren für die Trennung von Metallchelaten des Pyridin-2-aldehyd-2-chinolylhydrazons wurde den Bedingungen der Ringofentechnik angepaßt. Dabei kommt der große Unterschied derR _f -Werte der Chelate des Kobalts, des Kupfers, des Nickels und des Eisens(III) auf Aluminiumoxid vorteilhaft zur Geltung. Die Säurebeständigkeit des Kobaltkomplexes, die selektive Bildung von Chloridkomplexen der angeführten Metalle, die Verwendung spezifischer Sprühreagenzien für Cu und Fe wie Rubeanwasserstoffsäure und Kaliumrhodanid führten zu einer einfachen und raschen Feldmethode für die Spurenmetallanalyse. Die Mengenschätzung dieser vier Metalle auf 5 bis 12% Genauigkeit ist in weniger als 30 Minuten durchführbar. Die Erfassungsgrenze liegt für Ni bei 0,01g, für Cu und Fe bei 0,008g und für Co bei 0,005g. Andere Ionen stören nicht bis zum zehnfachen Überschuß. Die Eignung der Methode wurde an Süß- und Seewasserproben sowie an Algen geprüft.

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Presented at the International Symposium on Analytical Chemistry, July 1969, Birmingham, England.     

Anion exchangers functionalized by chelating reagents (AnChel) for preconcentration of trace elements: Capabilities and limitations

Summary Conventional anion exchangers (e.g., Adsorbex SAX, Amberlite IRA 410, Dowex 1X8, Lewatit MP 5080, TEAE cellulose) functionalized by means of sulfonated metal reagents (e.g., Arsenazo III, Eriochrome Red B, 8-hydroxyquinoline-5-sulfonic acid, Tiron and others) were investigated as collectors (AnChel) for analytical preconcentration of trace elements. In particular, the stability of AnChel strongly depending on competing anions, on the anion exchanger and on the metal reagent chosen, was characterized. Accordingly, for appropriate combinations of AnChel (e.g., Dowex 1X8/Arsenazo III) reagent distribution coefficients K_d in the range 10⁴ to 10⁵ (ml/g) could be attained on polystyrene-based anion exchangers even in concentrated salt solutions (e.g., 4 mol/l NaCl), but not on hydrophilic exchangers (e.g., SAX, TEAE cellulose). In general, the stability of AnChel against competing anions followed the order Cl^–>SO ₄ ^2– >NO ₃ ^– >ClO ₄ ^– . Reagent loadings of about 1 mmol/g (e.g., 8-hydroxyquinoline S) on the anion exchangers were obtainable. Trace metals precomplexed with the reagents cited could be separated (>90%) within 5 min and remobilized by acid (e.g. 2 mol/l HNO₃) within some 10 s (batch procedure). Using small columns filled with anion exchanger (e.g., 0.25 g Dowex 1X8) fast trace-matrix separations were carried out with 8-hydroxyquinoline S (Cu, Fe, In, Mn, Pb, Zn) in MgCl₂ solutions and with Arsenazo III (U, Th) in AlCl₃ solution, respectively. For subsequent trace determinations the flame-AAS (injection technique) was applied, except for Th and U [quantified by total reflection X-ray fluorescence (TXRF)].     

Metal bioaccumulation by the freshwater algaScenedesmus quadricauda

Bioaccumulation of six metals (Cu²⁺, Cu⁺, Mo⁶⁺, Mn²⁺, V⁵⁺, Ni²⁺) and their combinations by algaScenedesmus quadricauda was determined by using radio nuclide X-ray fluorescence (RXFA). The metals were added into the cultivation medium in concentrations corresponding with EC₅₀ value for each metal. The obtained results indicate that Ni²⁺, Cu²⁺ and Cu⁺ were accumulated in high amounts (20%, 17.5% and 15.19%) the Mo⁶⁺ ion (<0.2%) was accumulated in the lowest amount. For metal-metal interactions in accumulation of metal ions by algaS. quadricauda three types of answers were determined: inhibition (MoCu²⁺, Ni, Mn, V; VNi, Mn; MnNi, Cu²⁺, Cu⁺; Cu⁺Ni; Cu²⁺Ni; NiMn, V), enhancement (VCu⁺; Cu²⁺Mn;Cu⁺V, Mn; MnV; NiCu²⁺, Cu⁺) and neutral effect (VMo; Cu²⁺Mo; Cu⁺Mo; MuMo; NiMo).     

Analytische Multielement-Abtrennung aus hochreinem Aluminium mittels Chelat-Ionenaustauscher

Zusammenfassung Die analytische Multielement-Abtrennung (Bi, Ca, Cd, Cu, Fe, Mg, Mn, Ni, Sr, Zn) aus hochreinem Al (gelöst als Aluminat) an einem Chelat-Ionenaustauscher (Cellulose Hyphan) wird beschrieben. Hierbei reichern sich die Elementspuren aus Al-Lösungen mit Verteilungskoeffizienten von 10⁴ bis 10⁵ innerhalb weniger Minuten am Adsorber an. Die Spuren-/Matrix-Trennung geht mit Trennfaktoren von über 10⁵ vor sich. Nach Elution (2 M HCl) werden die benannten Elemente mittels Flammen-AAS (Injektionstechnik) bestimmt. Die Nachweisgrenzen (3 ) des Verbundverfahrens liegen zwischen 0,02 (Cd) und 1 g/ g (Bi), die relativen Standardabweichungen s_r zwischen 0,02 und 0,04. Zur Richtigkeitskontrolle wurden standardisierte Referenzmaterialien bzw. die instrumentelle Neutronen-aktivierungsanalyse eingesetzt.

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Analytical multi-element separation from high-purity aluminium by means of a chelating ion-exchanger

Summary The analytical preconcentration of trace elements (e.g., Bi, Ca, Cd, Cu, Fe, Mg, Mn, Ni, Sr, Zn) from high-purity Al (dissolved as aluminate) by means of a chelating ion-exchanger (cellulose Hyphan) is described. Using a fast batch-method, traces of metals can be enriched on the collector from Al solutions with distribution coefficients of the order 10⁴ to 10⁵. The preconcentration coefficients are of the same order of magnitude. After elution (2 M HCl) the trace elements are determined by flame-AAS (injection technique). With the combined procedure detection limits (3 ) in the range from 0.02 to 1 g/g can be attained for the elements mentioned. The accuracy is controlled by standard reference materials and by instrumental neutron activation analysis.

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Herrn Prof. Dr. H. Monien zum 60. Geburtstag gewidmet     

The synthesis and structure of the [2.2]paracyclophane cluster Ru6C(CO)13(μ 3-η 2:η 2:η 2-C16H16)(PPh3) and a study of the 1H-n.m.r. spectra of [2.2]paracyclophane and benzene clusters

Summary The [2.2]paracyclophane cluster, Ru₆C(CO)₁₄( ₃- ^{2 2 2}-C₁₆H₁₆) (1), undergoes reaction with Me₃NO and triphenylphosphine to yield Ru₆C(CO)₁₃( ₃- ^{2 2 2}-C₁₆H₁₆)(PPh₃) (2), which may also be produced from (1) by thermolysis with PPh₃ in THF. Compound (2) has been fully characterized in solution by spectroscopy and in the solid state by a single crystal X-ray diffraction analysis at 277 K, and its structure is compared with that of the parent cluster, (1). Using the same synthetic procedures, the tricyclohexylphosphine analogue, Ru₆C(CO)₁₃( ₃- ^{2 2 2}-C₁₆H₁₆)(PCy₃) (3), has also been prepared and characterized spectroscopically. A comparison of the chemical shifts of the 577-01 protons in the ¹H-n.m.r. spectra of compounds (1)–(3) together with a variety of other [2.2]paracyclophane and benzene clusters has been made.     

Stripping voltammetric determination of trace amounts of mercury using a carbon paste electrode modified with 2-mercapto-4(3H)-quinazolinone

A carbon paste electrode modified with 2-mercapto-4(3H)-quinazolinone was used for the voltammetric determination of mercury(II). Mercury was preconcentrated onto the surface of the modified electrode only by the complexing effect of the modifier without application of potential (i.e. in open-circuit conditions). After exchange of the medium, the accumulated amount of mercury(II) was determined by differential pulse anodic stripping voltammetry. The response depended on the concentration of mercury in the bulk solution, preconcentration time, and other parameters. The detection limit was 0.1 g 1^–1 Hg(II) for a preconcentration time of 15 min. Preconcentration for suitable times yielded a linear calibration graph from 0.5 to 6000 g 1^–1 Hg(II). For multiple determinations (5 runs), the relative standard deviation was 5% for a concentration of 100 g 1^–1 Hg(II). The proposed procedure was used to determine trace mercury in plant and sewage sludge samples with good results.On leave from Hainan University, Hainan Peoples Republic of China     

1D Polymeric copper(II) azido complexes. Synthesis,spectral and structural studies of [Cu(ethyl isonicotinate)2(N3)2]n and [Cu(methyl isonicotinate)2(NO3)(N3)]n complexes

Two new 1:2 polymeric complexes of copper(II) azide with ethyl isonicotinate (1) and methyl isonicotinate (2) have been synthesized and characterized by spectroscopic and crystallographic methods. The polymeric structure of complex (1) features six coordinated copper centers, a pair of trans-coordinated ligand molecules, and asymmetric ₂-1,1 and ₂-1,3-azido bridges resulting in a 1D chain structure. In complex (2), each copper atom which is located at an inversion center, is coordinated to a pair of trans ligand molecules, to the nitrogen atom of two -1,1-azido ligand and to an oxygen atom of a bridging (-O,O) nitrogen group. The i.r., electronic and e.s.r. spectra of the complexes are reported.     

Determination of chlorophenols in waste water using C18 reverse-phase enrichment prior to high resolution gaschromatography-mass spectrometry

Summary The analytical use of absorption chromatography using Sep-pak C₁₈ cartridges for the determination of trace amounts of lower chlorinated chlorophenols and chlorocresols in complex waste water samples is studied. A simple and efficient analysis at ppb (g/l) level has been developed and is demonstrated on municipal waste water receiving chlorophenols and chlorocresols from a chemical plant producing phenoxy herbicides. For higher halogenated phenols quantitative recovery is demonstrated for a sample volume of 1000 ml making preconcentration by means of C₁₈ absorption chromatography especially useful for trace analysis of these phenols.     

On-line trace preconcentration / matrix separation by high-performance flow atomic spectrometry (HPF-FLAME AAS)

Summary In HPF-atomic spectrometry a high-performance flow / hydraulic high-pressure nebulization (HPF / HHPN) system is used for sample introduction and aerosol generation. By employment of techniques common in HPLC or ion chromatography, on-line trace element preconcentration / matrix separation and atomic spectrometric trace determinations can be carried out. Preconcentration of trace elements in samples of drinking water allows determinations within the lower g/L region by using flame AAS. On-line trace element preconcentration / matrix separation from aluminium leads to detection limits of approx. 0.1 to 1 g/g within less than 3 min of total analysis time. Dependent on concentration and the element involved, the relative standard deviation amounts to approx. 2 to 4% (2.5 to 25 g/g traces/aluminium).Dedicated to Professor Dr. Wilhelm Fresenius on the occasion of his 80th birthday     

Transition metal complexes with 2-methyl-, 3-methyl-, and 4-methyl-piperidine dithiocarbamate as ligands

Summary A new series of manganese(III), cobalt(II), nickel(II), zinc(II), cadmium(II) and mercury(II) complexes with monomethylsubstituted dithiocarbamates as ligands has been synthesized and studied. Their structures are discussed in relation to their spectroscopic, magnetic and thermal properties. The dithio-ligands exhibit bidentate behaviour acting as S,Sdonors in all the complexes. In the far i.r. region particular attention is paid to a comparison of the spectra of the octahedral complexes with those of the other metal derivatives (12 metal to ligand molar ratio). The e.s.r. spectra are indicative of aD _2h symmetry in the cobalt(II) complexes.     

The electronic spectrum of acrylonitrile

The vapor absorption spectrum of acrylonitrile CH₂CHCN has been measured in the vacuum ultraviolet region. In addition, an all-valence-electron molecular orbital calculation has been used to calculate the electronic structure and spectrum of the molecule. On the basis of the MO calculation, as well as a vibrational analysis of the observed spectrum, several electronic transitions are assigned. The lowest energy absorption band (2107Å, = 150) is assigned as an n ^* transition. Absorption bands at 2030Å (=1600), 1725Å ( = 2100), and 1570Å ( = 1920) are assigned as 0–0 bands associated with transitions that are, respectively, ^*,^*, and ^* in character.

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Zusammenfassung Das UV-Absorptionsspektrum von dampfförmigen Acrylnitril wurde gemessen und eine CNDO/2-Rechnung für die Elektronenstruktur durchgeführt. Auf dieser Basis konnten unter Zuhilfenahme der Analyse der Schwingungsstruktur im beobachteten Spektrum mehrere Banden zugeordnet werden: die 2107-Å-Bande ( = 150) einem n^*-Übergang, die drei Banden bei 2030Å ( = 1600), 1725Å ( = 2100) und 1570 Å ( = 1920)0-0-Übergängen von ^*-, ^*- bzw. ^*-Banden.

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Résumé Mesure du spectre d'absorption en phase vapeur de l'acrilonitrile CH₂CHCN dans la région de l'ultraviolet. Par ailleurs, la structure électronique et le spectre de la molécule ont été calculés à l'aide d'une méthode des orbitales moléculaires semi-empirique pour tous les électrons de valence. Sur cette base, ainsi que sur une analyse vibrationnelle du spectre expérimental, on procède à l'attribution de plusieurs transitions électroniques. La bande d'absorption de plus basse énergie (2107 Å, = 150) est attribuée à une transition n ^*. Les bandes d'absorption à 2030Å ( = 1600), 1275Å ( = 2100) et 1570Å ( = 1920) sont considérées comme des bandes 0 - 0 associées à des transitions ^*, ^* et ^* respectivement.