DOCSLIB.ORG

Complexes of Glycolic Acid with Nitrogen Isolated in Argon Matrices

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Complexes of Glycolic Acid with Nitrogen Isolated in Argon Matrices molecules Article Complexes of Glycolic Acid with Nitrogen Isolated in Argon Matrices. I. Structures and Thermal Effects Iwona Kosendiak 1, Jussi M.E. Ahokas 2 , Justyna Krupa 1 , Jan Lundell 2,* and Maria Wierzejewska 1,* 1 Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw, Poland 2 Department of Chemistry, University of Jyvaskyla, P.O.Box 35, 40014 Jyvaskyla, Finland * Correspondence: jan.c.lundell@jyu.fi (J.L.); [email protected] (M.W.); Tel.: +358-40-744-5270 (J.L.); +48-71-375-7332 (M.W.) Received: 29 July 2019; Accepted: 5 September 2019; Published: 7 September 2019 Abstract: Molecular complexes between glycolic acid and nitrogen were studied in a low-temperature argon matrix with FTIR spectroscopy, and supported by MP2 and BLYPD3 calculations. The calculations indicate 11 and 10 stable complex structures at the MP2 and BLYPD3 levels of theories, respectively. However, only one hydrogen-bonded complex structure involving the most stable SSC conformer of glycolic acid was found experimentally, where the nitrogen molecule is bound with the carboxylic OH group of the SSC conformer. The complex shows a rich site structure variation upon deposition of the matrix in different temperatures and upon annealing experiments, which provide interesting prospects for site-selective chemistry. Keywords: hydrogen bond; matrix isolation; carboxylic acid; computational chemistry; vibrational spectroscopy 1. Introduction Hydrogen bonding is a significant non-covalent interaction that plays an important role in many areas of biology and chemistry [1,2]. Weakly bound molecular complexes with hydrogen bond or van der Waals interactions are frequently encountered in atmospheric chemistry and are known to affect both chemical and photochemical processes [3–5]. In complexes, the electronic, vibrational and rotational levels are disturbed as a result of interaction between complex subunits, and this leads to changes in spectral and photochemical characteristics of the complex components. On the other hand, weakly bound complexes frequently represent shallow energy minima on their potential energy surfaces, which lead to thermodynamic instability of such species at room temperature. From this point of view, the low temperature matrix isolation technique coupled with different spectroscopic methods is a very useful technique to trap and to study weakly bound complexes [6,7]. Recently, it was demonstrated that matrix isolation technique connected with computational studies is a powerful approach to study hydrogen bonds and other intermolecular interactions in complexes involving atmospheric constituents or species related to tropospheric IR-induced chemistry [8–14]. Glycolic acid (GA), the simplest α-hydroxycarboxylic acid with two OH groups, is capable of forming both intra- and intermolecular hydrogen bonds. As such, GA is a model species to study in order to understand how competing OH-groups in the molecule affect the chemical reactivity and capability to form molecular complexes. Several reports on monomeric GA isolated in low-temperature matrices as well as its transformations have appeared in the literature [15–20]. The structures of the three most stable GA species are presented in Figure1. Among the monomer structures, the most stable conformer is the SSC form, which is stabilized by the O–H O intramolecular hydrogen bond. This ··· conformer is present in the gas phase and in low-temperature matrices with an estimated population Molecules 2019, 24, 3262; doi:10.3390/molecules24183262 www.mdpi.com/journal/molecules Molecules 2019, 24, x FOR PEER REVIEW 2 of 13 Molecules 2019, 24, 3262 2 of 13 intramolecular hydrogen bond. This conformer is present in the gas phase and in low-temperature at roommatrices temperature with an ofestim ca.ated 95%. population A small amount at room of temperature two less stable of ca. GAC 95%. and A small AAT amount conformers of two has less also stable GAC and AAT conformers has also been detected [19,20]. been detected [19,20]. FigureFigure 1. Structures 1. Structures of theof the three three most most stable stable conformers conformers ofof glycolicglycolic acid monomer. monomer. ContraryContrary to the to the monomeric monomeric GA, GA, only only two two studies studies on on GA GA complexescomplexes in low low-temperature-temperature matrices matrices havehave appeared appeared in literature. in literature. Recently, Recently, a study a study on on GA GA dimers dimers revealed revealed for for the the first first time time information information on threeon cyclic three GA cyclic dimers GA dimers identified identified in an argonin an argon matrix matrix [21]. [21]. All of All these of these dimers dimers were were formed formed between between SSC conformers:SSC conformers: one dimer one with dimer hydrogen with hydrogen bonds between bonds between the two the carboxylic two carboxylic OH groups, OH onegroups, structure one withstructure hydrogen with bonds hydrogen between bonds the two between alcoholic the two OH alcoholic groups and OH a groups mixed structureand a mixed with structure one OH with group fromone the OH carboxylic group from group the actingcarboxylic as proton group acting donor as and proton the alcoholicdonor and OH the groupalcoholic on OH the group other subuniton the actingother as protonsubunit acceptor. acting as Molecularproton acceptor. complexes Molecular between complexes GA and between molecular GA nitrogenand molecular were nitrogen identified in a studywere identifi applyinged Ramanin a study spectroscopy applying Raman for argon-trapped spectroscopy species for argon upon-trapped high vibrational species upon excitation high experimentsvibrational [22 excitation]. In that experiments study, nitrogen [22]. In was that found study, to nitrogen form complexes was found with to form two complexes GA conformers with two GA conformers (SSC and AAT) in low temperature argon environment. However, this study did (SSC and AAT) in low temperature argon environment. However, this study did not scrutinise the not scrutinise the actual molecular complex structures involved but only made conclusions of actual molecular complex structures involved but only made conclusions of different GA N systems … ··· 2 involveddifferent based GA onN their2 systems behaviour involved upon based 532 on nm their irradiation. behaviour upon 532 nm irradiation. These Raman spectroscopy combined with visible light irradiation experiments acted as a These Raman spectroscopy combined with visible light irradiation experiments acted as a prelude prelude to our study presented here. In this paper, we present results of a combined study employing to our study presented here. In this paper, we present results of a combined study employing both both theoretical methods and FTIR matrix isolation studies on complexes formed between glycolic theoretical methods and FTIR matrix isolation studies on complexes formed between glycolic acid and acid and nitrogen molecule. The target is to study and to identify the 1:1 complexes GA forms with nitrogen molecule. The target is to study and to identify the 1:1 complexes GA forms with molecular molecular nitrogen. This research is important in order to understand which type of complexes can nitrogen.be formed, This researchif such species is important are experimentally in order to understanddetected, and which, as these type formed of complexes complexes can are be used formed, as if suchprecursors species arefor near experimentally-infrared irradiation detected, experiments and, as these, if their formed photo complexes-induced arechemistry used as differ precursors from for near-infraredisolated GA monomers. irradiation The experiments, study on the if NIR their irradiated photo-induced GA-N2 complexes chemistry is di reportedffer from separately isolated in GA monomers.a following The paper study taking on the advantage NIR irradiated of the results GA-N 2presentedcomplexes here. is reported separately in a following paper taking advantage of the results presented here. 2. Experimental and Computational Details 2. Experimental and Computational Details The matrix samples were prepared by passing mixtures of high purity argon (Messer, 5.0) and nitrogenThe matrix (Messer, samples 6.0) with were the prepared N2/Ar ratios by passing of 1/4000 mixtures through the of highglass purityU-tube argonwith glycolic (Messer, acid 5.0) (GA) and nitrogensituated (Messer, outside 6.0) the with cryostat the N chamber.2/Ar ratios Optimizing of 1/4000 throughthe deposition the glass temperature U-tube with and glycolicmatrix flow acid rate (GA) situatedit was outside possible the cryostatto obtain chamber. matrices Optimizing containing thenearly deposition exclusively temperature monomeric and GA matrix and flow GA… rateN2 it was possiblecomplexes to of obtain 1:1 stoichiometry. matrices containing The GA/N nearly2/Ar exclusively gaseous mixtures monomeric were GA deposited and GA ontoN a complexescold CsI ··· 2 of 1:1window stoichiometry. kept at 15 The K GAor 18/N 2K/Ar in gaseousan APD- mixturesCryogenics were (ARS deposited-2HW) closed onto acycle cold cryostat. CsI window Annealing kept at 15 Kexperiments or 18 K in an were APD-Cryogenics performed upon (ARS-2HW) the deposited closed samples cycle cryostat.at 33 K. The Annealing sample experimentstemperature was were performedmaintained upon by the a Scientific deposited Instruments samples at 9700 33 K. temperature The sample controller temperature equipped was maintained with a silicon by
Load more

Recommended publications
  • Matrix-Isolation FTIR Study of Azidoacetone and Azidoacetonitrile M
    LOW TEMPERATURE PHYSICS VOLUME 29, NUMBER 9–10 SEPTEMBER–OCTOBER 2003 Matrix-isolation FTIR study of azidoacetone and azidoacetonitrile M. Frankowski,* B. S. Fox, A. M. Smith-Gicklhorn, M. K. Beyer, and V. E. Bondybey** Institute of Physical and Theoretical Chemistry, Technical University of Munich, Garching 85747, Germany M. Algarra and M. L. Costa CEFITEC, Department of Physics, Fac. Sciences and Technology, Universidade Nova de Lisboa, Caparica P-2829-516, Portugal P. Rodrigues and M. T. Barros CQFB, Department of Chemistry, Fac. Sciences and Technology, Universidade Nova de Lisboa, Caparica P-2829-516, Portugal M. N. D. S. Cordeiro REQUIMTE, Department of Chemistry, Fac. Sciences, Universidade do Porto, Porto 4169-007, Portugal Fiz. Nizk. Temp. 29, 1140–1146 ͑September–October 2003͒ Azidoacetonitrile (N3CH2CN) and azidoacetone (N3CH2COCH3) are studied by matrix-isolation FTIR spectroscopy in solid neon, argon, and nitrogen. The IR spectra calculated using the density-fuctional theoretical method are discussed in comparison with the experimental data. Significant broadening of the recorded azide bands indicate an awkward fit of these compounds into the solid environment. The strongest absorption is observed for both compounds in the regions of asymmetric and symmetric stretches of the N3 azide group. Strong band splittings in the N3 asymmetric stretch region can be most likely explained by very strong Fermi resonances with the CN stretch and combinations and overtones of the numerous lower- frequency vibrational modes. © 2003 American Institute of Physics. ͓DOI: 10.1063/1.1619361͔ INTRODUCTION EXPERIMENTAL Sample preparation Organic azides are useful reagents in many fields.1–3 Their strongly exothermic reactions make them useful as Azidoacetonitrile was synthesized from chloroacetoni- 4 propellants.
    [Show full text]
  • Aqueous Pka Prediction for Tautomerizable Compounds Using Equilibrium Bond Lengths
    ARTICLE https://doi.org/10.1038/s42004-020-0264-7 OPEN Aqueous pKa prediction for tautomerizable compounds using equilibrium bond lengths Beth A. Caine1,2, Maddalena Bronzato3, Torquil Fraser3, Nathan Kidley3, Christophe Dardonville 4 & ✉ Paul L.A. Popelier 1,2 1234567890():,; The accurate prediction of aqueous pKa values for tautomerizable compounds is a formidable task, even for the most established in silico tools. Empirical approaches often fall short due to a lack of pre-existing knowledge of dominant tautomeric forms. In a rigorous first-principles approach, calculations for low-energy tautomers must be performed in protonated and deprotonated forms, often both in gas and solvent phases, thus representing a significant computational task. Here we report an alternative approach, predicting pKa values for her- bicide/therapeutic derivatives of 1,3-cyclohexanedione and 1,3-cyclopentanedione to within just 0.24 units. A model, using a single ab initio bond length from one protonation state, is as accurate as other more complex regression approaches using more input features, and outperforms the program Marvin. Our approach can be used for other tautomerizable spe- cies, to predict trends across congeneric series and to correct experimental pKa values. 1 Department of Chemistry, University of Manchester, Manchester, UK. 2 Manchester Institute of Biotechnology (MIB), 131 Princess Street, Manchester, UK. 3 Syngenta AG, Jealott’s Hill, Warfield, Bracknell RG42 6E7, UK. 4 Instituto de Química Médica, IQM–CSIC, C/Juan de la Cierva 3, Madrid 28006, Spain. ✉ email: [email protected] COMMUNICATIONS CHEMISTRY | (2020) 3:21 | https://doi.org/10.1038/s42004-020-0264-7 | www.nature.com/commschem 1 ARTICLE COMMUNICATIONS CHEMISTRY | https://doi.org/10.1038/s42004-020-0264-7 pproximately 21% of the compounds that make up (http://vcclab.org), Marvin (http://www.chemaxon.com) and pharmaceutical databases are said to exist in two or more Pallas (www.compudrug.com)) on 248 compounds of the Gold A 1 12 tautomeric forms .
    [Show full text]
  • Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Ions
    J. Phys. Chem. A 2000, 104, 3655-3669 3655 Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Ions. 5. PAHs Incorporating a Cyclopentadienyl Ring† D. M. Hudgins,* C. W. Bauschlicher, Jr., and L. J. Allamandola NASA Ames Research Center, MS 245-6, Moffett Field, California 94035 J. C. Fetzer CheVron Research Company, Richmond, California 94802 ReceiVed: NoVember 5, 1999; In Final Form: February 9, 2000 The matrix-isolation technique has been employed to measure the mid-infrared spectra of the ions of several polycyclic aromatic hydrocarbons whose structures incorporate a cyclopentadienyl ring. These include the cations of fluoranthene (C16H10), benzo[a]fluoranthene, benzo[b]fluoranthene, benzo[j]fluoranthene, and benzo- [k]fluoranthene (all C20H12 isomers), as well as the anions of benzo[a]fluoranthene and benzo[j]fluoranthene. With the exception of fluoranthene, which presented significant theoretical difficulties, the experimental data are compared to theoretically calculated values obtained using density functional theory (DFT) at the B3LYP/ 4-31G level. In general, there is good overall agreement between the two data sets, with the positional agreement between the experimentally measured and theoretically predicted bands somewhat better than that associated with their intensities. The results are also consistent with previous experimental studies of polycyclic aromatic hydrocarbon ions. Specifically, in both the cationic and anionic species the strongest ion bands typically cluster in the 1450 to 1300 cm-1 range, reflecting an order-of-magnitude enhancement in the CC stretching and CH in-plane bending modes between 1600 and 1100 cm-1 in these species. The aromatic CH out-of- plane bending modes, on the other hand, are usually modestly suppressed (e 2x - 5x) in the cations relative to those of the neutral species, with the nonadjacent CH modes most strongly affected.
    [Show full text]
  • A MATRIX ISOLATION SPECTROSCOPIC INVESTIGATION of the REACTION PRODUCTS of TRANSITION METAL CENTRES with ETHENE and WATER By
    A MATRIX ISOLATION SPECTROSCOPIC INVESTIGATION OF THE REACTION PRODUCTS OF TRANSITION METAL CENTRES WITH ETHENE AND WATER by MATTHEW G. K. THOMPSON A thesis submitted to the Department of Chemistry in conformity with the requirements for the degree of Doctor of Philosophy Queen’s University Kingston, Ontario, Canada November 2007 Copyright © Matthew Gary Karl Thompson, 2007 Abstract The reaction products of thermally generated atomic V with ethene and ethene isotopomers have been investigated by matrix isolation ultraviolet visible and Fourier transform infrared (FTIR) spectroscopy. When V is deposited into matrices of pure Ar, evidence for V and V2 are present in the UV-visible absorption spectra. Addition of trace amounts of ethene results in the elimination of absorptions due to V2 on deposition, likely due to the formation of … V (C2H4) van der Waals complexes on matrix condensation. Irradiation of matrices containing V and trace C2H4 in Ar, with light corresponding to atomic V electronic excitations, eliminates all UV-visible absorptions due to atomic V in the matrix. Infrared analysis of matrices containing V and C2H4 give evidence for a new product on deposition, consistent with a kinetically formed H-V-C2H3 isomer. Following further irradiation of the matrix, several new products of C-H bond insertion by the metal atom, including additional H-V-C2H3 conformational 2 isomers, and H2V(η -C2H2) products are observed in the infrared spectrum. Additionally, the formation of ethane is evident as a major product immediately following deposition of V + C2H4 + H2O in Ar. The formation of this product is consistent with alkene insertion into the V-H bond of an H-V-OH intermediate, followed by a photo-induced elimination to give C2H6.
    [Show full text]
  • DFT and QTAIM Study of the Tetra-Tert ... -.:. Michael Pittelkow
    Journal of Molecular Structure 1026 (2012) 127–132 Contents lists available at SciVerse ScienceDirect Journal of Molecular Structure journal homepage: www.elsevier.com/locate/molstruc DFT and QTAIM study of the tetra-tert-butyltetraoxa[8]circulene regioisomers structure ⇑ Gleb V. Baryshnikov a, Boris F. Minaev a, , Valentina A. Minaeva a,b, Alina T. Baryshnikova a, Michael Pittelkow c a Bohdan Khmelnytsky National University, 18031 Cherkasy, Ukraine b Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden c Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark highlights " Tetra-tert-butyltetraoxa[8]circulene regioisomers were studied by DFT method. " Electronic density distribution was calculated by the QTAIM method. " The presence of stabilizing non-valence bonds is detected by X-ray experiment. " The HÁÁÁH contacts are dynamically unstable due to high ellipticity. " The energy of the HÁÁÁH and CHÁÁÁO contacts was estimated by the Espinosa equation. article info abstract Article history: The recently synthesized tetra-tert-butyltetraoxa[8]circulene regioisomers characterized by unusual Received 6 March 2012 solution-state aggregation behavior are calculated at the density functional theory (DFT) level with the Received in revised form 24 May 2012 quantum theory of atoms in molecules (QTAIMs) approach to the electron density distribution analysis. Accepted 24 May 2012 The presence of stabilizing intramolecular hydrogen bonds and hydrogen–hydrogen interactions in the Available online 31 May 2012 studied molecules is predicted and the energies of these interactions are estimated with QTAIM. Occur- rence of the CHÁÁÁO bonds is detected by the single-crystal X-ray analysis for two regioisomers, obtained Keywords: in high purity.
    [Show full text]
  • Formation of Β-Cyclodextrin Complexes in an Anhydrous Environment
    JMolModel (2016) 22:207 DOI 10.1007/s00894-016-3061-6 ORIGINAL PAPER Formation of β-cyclodextrin complexes in an anhydrous environment Hocine Sifaoui1 & Ali Modarressi2 & Pierre Magri2 & Anna Stachowicz-Kuśnierz3 & Jacek Korchowiec3 & Marek Rogalski2 Received: 16 December 2015 /Accepted: 3 July 2016 # The Author(s) 2016. This article is published with open access at Springerlink.com Abstract The formation of inclusion complexes of β- Keywords β-Cyclodextrin . Differential scanning cyclodextrin was studied at the melting temperature of guest calorimetry . Inclusion complexes . Polyaromatics . Organic compounds by differential scanning calorimetry. The com- acids . Molecular modeling plexes of long-chain n-alkanes, polyaromatics, and organic acids were investigated by calorimetry and IR spectroscopy. The complexation ratio of β-cyclodextrin was compared with results obtained in an aqueous environment. The stability and Introduction structure of inclusion complexes with various stoichiometries were estimated by quantum chemistry and molecular dynam- Many lipophilic drug molecules display low bioavailability ics calculations. Comparison of experimental and theoretical that hinder their efficacy [1]. Cyclodextrins, which form stable results confirmed the possible formation of multiple inclusion complexes with numerous molecules, are used to improve complexes with guest molecules capable of forming hydrogen aqueous solubility and bioavailability. β-Cyclodextrin (β- bonds. This finding gives new insight into the mechanism of CD) is composed of seven glucopyranose units forming a formation of host–guest complexes and shows that hydropho- cyclic, cone-shaped cavity with a hydrophilic outer surface bic interactions play a secondary role in this case. and a relatively hydrophobic inner surface [2]. This molecular structure of β-CD allows the formation of complexes with a large variety of organic molecules of different shape and po- larity [3–8].
    [Show full text]
  • Predikce Hodnot Pka Na Základě EEM Atomových Nábojů
    MASARYKOVA UNIVERZITA PRˇ I´RODOVEˇ DECKA´ FAKULTA NA´ RODNI´ CENTRUM PRO VY´ZKUM BIOMOLEKUL Diplomova´pra´ce BRNO 2013 STANISLAV GEIDL MASARYKOVA UNIVERZITA PRˇ I´RODOVEˇ DECKA´ FAKULTA NA´ RODNI´ CENTRUM PRO VY´ZKUM BIOMOLEKUL Predikce hodnot pKa na za´kladeˇ EEM atomovy´ch na´boju˚ Diplomova´pra´ce Stanislav Geidl Vedoucı´pra´ce: prof. RNDr. Jaroslav Kocˇa, DrSc. Konzultant: RNDr. Radka Svobodova´Varˇekova´, Ph.D. Brno 2013 Bibliograficky´za´znam Autor: Bc. Stanislav Geidl Prˇı´rodoveˇdecka´fakulta, Masarykova univerzita Na´rodnı´centrum pro vy´zkum biomolekul Na´zev pra´ce: Predikce hodnot pKa na za´kladeˇEEM atomovy´ch na´boju˚ Studijnı´program: Biochemie Studijnı´obor: Chemoinformatika a bioinformatika Vedoucı´pra´ce: prof. RNDr. Jaroslav Kocˇa, DrSc. Akademicky´rok: 2012/2013 Pocˇet stran: xi + 78 Klı´cˇova´slova: disociacˇnı´konstanta, pKa, QSPR, vı´cerozmeˇrna´linea´rnı´ regrese, atomove´ na´boje, kvantova´ mechanika, EEM, fenoly, karboxylove´kyseliny Bibliographic Entry Author: Bc. Stanislav Geidl Faculty of Science, Masaryk University National Centre for Biomolecular Research Title of Thesis: Predicting pKa values from EEM atomic charges Degree Programme: Biochemistry Field of Study: Chemoinformatics and Bioinformatics Supervisor: prof. RNDr. Jaroslav Kocˇa, DrSc. Academic Year: 2012/2013 Number of Pages: xi + 78 Keywords: dissociation constant, pKa, QSPR, multilinear regres- sion, partial atomic charge, quantum mechanics, EEM, phenols, carboxilic acids Abstrakt Disociacˇnı´ konstanta pKa je velmi du˚lezˇitou vlastnostı´ molekuly, a proto je vy´voj spolehlivy´ch a rychly´ch metod pro predikci pKa jednou z klı´cˇovy´ch oblastı´ vy´zkumu. Tato pra´ce zjisˇt’uje, jestli lze predikovat pKa pomocı´QSPR modelu˚ vyuzˇı´vajı´cı´ch empiricke´atomove´na´boje, konkre´tneˇna´boje vypocˇı´tane´metodou EEM (Electronegativity Equalization Method).
    [Show full text]
  • Multiwfn - a Multifunctional Wavefunction Analyzer
    Multiwfn - A Multifunctional Wavefunction Analyzer - Software Manual with abundant tutorials and examples in Chapter 4 Version 3.3.8 2015-Dec-1 http://Multiwfn.codeplex.com Tian Lu [email protected] Beijing Kein Research Center for Natural Sciences (www.keinsci.com) !!!!!!!!!! ALL USERS MUST READ !!!!!!!!!! I know, most people, including myself, are unwilling to read lengthy manual. Since Multiwfn is a heuristic and very user-friendly program, it is absolutely unnecessary to read through the whole manual before using it. However, you should never skip reading following content! 1. The BEST way to get started quickly is directly reading Chapter 1 and the tutorials in Chapter 4. After that if you want to learn more about Multiwfn, then read Chapters 2 and 3. Note that the tutorials and examples given in Chapter 4 only cover the most frequently used functions of Multiwfn. Some application skills are described in Chapter 5, which may be useful for you. 2. Different functions of Multiwfn require different type of input file, please read Section 2.5 for explanation. 3. If you do not know how to copy the output of Multiwfn from command-line window to a plain text file, consult Section 5.4. If you do not know how to enlarge screen buffer size of command-line window of Windows system, consult Section 5.5. 4. If the error “No executable for file l1.exe” appears in screen when Multiwfn is invoking Gaussian, you should set up Gaussian environment variable first. For Windows version, you can refer Appendix 1. (Note: Most functions in Multiwfn DO NOT require Gaussian installed on your local machine) 5.
    [Show full text]
  • Matrix Isolation and Computational Study of Isodifluorodibromomethane (F2 Cbr-Br): a Route to Br2 Formation in Cf2 Br2 Photolysis
    Bowling Green State University ScholarWorks@BGSU Chemistry Faculty Publications Chemistry 2010 Matrix Isolation and Computational Study of Isodifluorodibromomethane (F2 Cbr-Br): A Route to Br2 Formation in Cf2 Br2 Photolysis Alexander N. Tarnovsky Bowling Green State University, [email protected] Lisa George Aimable Kalume Patrick Z. El-Khoury Scott A. Reid Follow this and additional works at: https://scholarworks.bgsu.edu/chem_pub Part of the Chemistry Commons Repository Citation Tarnovsky, Alexander N.; George, Lisa; Kalume, Aimable; El-Khoury, Patrick Z.; and Reid, Scott A., "Matrix Isolation and Computational Study of Isodifluorodibromomethane (F2 Cbr-Br): A Route to Br2 Formation in Cf2 Br2 Photolysis" (2010). Chemistry Faculty Publications. 26. https://scholarworks.bgsu.edu/chem_pub/26 This Article is brought to you for free and open access by the Chemistry at ScholarWorks@BGSU. It has been accepted for inclusion in Chemistry Faculty Publications by an authorized administrator of ScholarWorks@BGSU. THE JOURNAL OF CHEMICAL PHYSICS 132, 084503 ͑2010͒ Matrix isolation and computational study of isodifluorodibromomethane „F2CBr–Br…: A route to Br2 formation in CF2Br2 photolysis Lisa George,1 Aimable Kalume,1 Patrick Z. El-Khoury,2 Alexander Tarnovsky,2 and ͒ Scott A. Reid1,a 1Department of Chemistry, Marquette University, Milwaukee, Wisconsin 53201-1881, USA 2Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA ͑Received 29 November 2009; accepted 26 January 2010; published online 22 February 2010͒ ͑ ͒ The photolysis products of dibromodifluoromethane CF2Br2 were characterized by matrix isolation infrared and UV/Visible spectroscopy, supported by ab initio calculations. Photolysis at ͑ϳ ͒ ϳ wavelengths of 240 and 266 nm of CF2Br2 :Ar samples 1:5000 held at 5 K yielded ͑ ͒ iso-CF2Br2 F2CBrBr , a weakly bound isomer of CF2Br2, which is characterized here for the first time.
    [Show full text]
  • Arghya Chakraborty
    Electronic Characterization of Mass-Selected Acyclic, Polycyclic and Oxygenated Hydrocarbons in Neon Matrices INAUGURALDISSERTATION zur Erlangung der Würde eines Doktors der Philosophie vorgelegt der Philosophisch-Naturwissenschaftlichen Fakultät der Universität Basel von Arghya Chakraborty aus Westbengal, Indien Basel, 2016 Originaldokument gespeichert auf dem Dokumentenserver der Universität Basel edoc.unibas.ch 1 Genehmigt von der Philosophisch-Naturwissenschaftlichen Fakultät auf antrag von Dissertationsleiter: Prof. Dr. John. P. Maier Korreferent: Prof. Dr. Stefan Willitsch Basel, 23 Februar 2016 Prof. Dr. J. Schibler Dekan 2 Electronic Characterization of Mass-Selected Acyclic, Polycyclic and Oxygenated Hydrocarbons in Neon Matrices PhD THESIS Of ARGHYA CHAKRABORTY Basel 2016 3 4 Acknowledgements A researcher needs a healthy working atmosphere to be productive. The work and personal life in Basel would not have been so pleasant without the guidance and support of several individuals. First of all, I would like to thank Prof. John Paul Maier for his constant endorsement, supervision and providing world class experimental facilities in laboratory. Beside science, I have learned lots of technical skills from him and hopefully will apply them in my entire career. I am very much thankful to Prof. Stefan Willitsch for being the co-referee of my thesis. Prof. Markus Meuwly is thanked for accepting to be the chair in my PhD defense. Heartiest thank of mine goes to Dr. Jan Fulara for teaching me the essentials of the matrix isolation set-up, sharing his deep knowledge on spectroscopy and helping with his computational skill. Special thanks are also addressed to Dr. Corey Rice for his advices, explanations and experimental ideas. I am highly privileged to him for being the proof reader of my thesis.
    [Show full text]
  • On the Covalent Character of Rare Gas Bonding Interactions: a New Kind of Weak Interaction” by Wenli Zou, Davood Nori-Shargh, and James E
    Supporting Information to the article entitled “On the covalent character of rare gas bonding interactions: a new kind of weak interaction” by Wenli Zou, Davood Nori-Shargh, and James E. Boggs Table S1. Equilibrium geometries (bond length in Å and bond angle in degree) of some rare gas containing systems. All of them have C ∞v symmetry except HeB(CH) 3 with C 3v . No. Mol. State Structure parameters Ref. 1 FHeO - 1Σ+ He-O=1.100, He-F=1.621 61 2 HHeF 1Σ+ He-H=0.818, He-F=1.418 63 3 HArF 1Σ+ Ar-H=1.329, Ar-F=1.967 6 4 HeCuF 1Σ+ He-Cu=1.659, Cu-F=1.732 26 5 HeAgF 1Σ+ He-Ag=2.143, Ag-F=1.967 26 6 HeAuF 1Σ+ He-Au=1.841, Au-F=1.904 26 7 NeCuF 1Σ+ Ne-Cu=2.172, Cu-F=1.738 26 8 NeAgF 1Σ+ Ne-Ag=2.700, Ag-F=1.974 26 9 NeAuF 1Σ+ Ne-Au=2.444, Au-F=1.917 26 10 ArCuF a) 1Σ+ Ar-Cu=2.219, Cu-F=1.753 12 11 ArAgF a) 1Σ+ Ar-Ag=2.558, Ag-F=1.986 13 12 ArAuF a) 1Σ+ Ar-Au=2.391, Au-F=1.918 14 13 KrCuF a) 1Σ+ Kr-Cu=2.316, Cu-F=1.745 11 14 KrAgF a) 1Σ+ Kr-Ag=2.594, Ag-F=1.984 b) 10 15 KrAuF a) 1Σ+ Kr-Au=2.460, Au-F=1.918 10 16 XeCuF a) 1Σ+ Xe-Cu=2.430, Cu-F=1.745 9 17 XeAgF a) 1Σ+ Xe-Ag=2.666, Ag-F=1.983 8 18 XeAuF a) 1Σ+ Xe-Au=2.543, Au-F=1.918 7 19.a HePtF 2Σ+ He-Pt=1.828, Pt-F=1.881 31 19.b 2Π He-Pt=1.860, Pt-F=1.862 19.c 2∆ He-Pt=1.798, Pt-F=1.900 20 HePtXe 1Σ+ He-Pt=1.818, Xe-Pt=2.509 33 1 21 HeB(CH) 3 A1 He-B=1.355, B-C=1.493, C-H=1.066, 32 C-B-He=143.7, H-C-B=161.4 22 HeBeO 1Σ+ He-Be=1.522, Be-O=1.330 25 23 NeBeO 1Σ+ Ne-Be=1.798, Be-O=1.339 37 24 ArBeO 1Σ+ Ar-Be=2.076, Be-O=1.341 37 25 KrBeO 1Σ+ Kr-Be=2.211, Be-O=1.343 37 26 XeBeO 1Σ+ Xe-Be=2.385, Be-O=1.344 37 a) Experimental geometries.
    [Show full text]
  • "Carbon-Nitrogen Chain Molecules in the Laboratory and in Interstellar
    CARBON-NITROGEN CHAIN MOLECULES IN THE LABORATORY AND IN INTERSTELLAR MEDIUM BY ROBERT KOŁ OS Institute of Physical Chemistry of the Polish Academy of Sciences Warsaw 2003 ISBN 83-913520-4-8 2 to the memory of my Father 3 4 Preface Science sans conscience n’est que ruine de l’âme. –Rabelais (1532) The simplest and broadest definition of the interstellar matter – “everything but stars” – may be misleading. Is Earth a piece of it? Are humans the interstellar matter, with all material products of the terrestrial civilization? Avoiding the perils of semantics, I will rather use the term in its narrow sense. In what follows, it will primarily be applied to immense clouds of gas and dust, without which the stars would have nothing to be born from, and – when their time comes – nothing to disperse into. It is only 35 years now, since an important, yet largely unnoticed discovery has been made. The interstellar matter was found to be more than just hydrogen, helium, mineral dust, and a small admixture of heavier atoms, their ions, and few simplest diatomics – as was originally believed. In addition to this blend (not very promising for a chemist) the presence of quite complex organic molecules was revealed. By plain chemical standards, some of the compounds given the “interstellar” tag may seem bizzare (or useless), like the largest ones: rod-shaped polyacetylenic nitriles. Still, all these merit our closest attention. If a molecule is abundant enough to show up in the interstellar medium – in spite of present rudimentary detection methods – then it inevitably has to be conceived as one of most important arrangements of atoms in the Galaxy, and possibly also in the entire Universe.
    [Show full text]