0000000001076612
AUTHOR
Risto S. Laitinen
Electronic Structures and Molecular Properties of Chalcogen Nitrides Se2N2 and SeSN2
The electronic structures and molecular properties of S2N2 as well as the currently unknown chalcogen nitrides Se2N2 and SeSN2 have been studied using various ab initio and density functional methods. All molecules share a qualitatively similar electronic structure and can be primarily described as 2π-electron aromatics having minor singlet diradical character of 6−8% that can be attributed solely to the nitrogen atoms. This diradical character is manifested in the prediction of their molecular properties, in which coupled cluster and multiconfigurational approaches, as well as density functional methods, show the best performance. The conventional ab initio methods RHF and MP2 completely f…
Computational investigations of 18-electron triatomic sulfur–nitrogen anions
MRCI-SD/def2-QZVP and PBE0/def2-QZVP calculations have been employed for the analysis of geometries, stabilities, and bonding of isomers of the 18-electron anions N2S2−, NS2−, and NSO−. Isomers of the isoelectronic neutral molecules SO2, S2O, S3, and O3 are included for comparison. The sulfur-centered acyclic NSN2−, NSS−, and NSO− anions are the most stable isomers of their respective molecular compositions. However, the nitrogen-centered isomers SNS− and SNO− lie close enough in energy to their more stable counterparts to allow their occurrence. The experimental structural information, where available, is in good agreement with the optimized bond parameters. The bonding in all investigate…
Acyclic imidoselenium(ii) dihalides: synthesis and X-ray structures of ClSe[N(But)Se]nCl (n = 1, 2)
The reaction of SeCl2 with tert-butylamine in THF yields the acyclic imidoselenium(II) dichlorides ClSeN(But)NSeCl and ClSeN(But)SeN(But)SeCl, in addition to the six-membered ring Se3(NBut)3.
Ab initio molecular orbital study of SenS4−nN4 (n = 0−4)
Abstract We report an ab initio study of Se n S 4− n N 4 ( n = 0−4). The full geometry optimization for each molecule was performed at the Hartree-Fock level of theory involving the MIDI-4 ∗ basis sets for atomic orbitals. The correction for electron correlation was carried out for optimized geometries by utilizing the second-order Moller-Plesset (MP2) perturbation theory. The fundamental vibrations calculated for all molecular species verified that all molecules lie at the local minima. All molecules showed cage structures similar to those observed experimentally for S 4 N 4 and Se 4 N 4 . The calculated bond parameters of S 4 N 4 and Se 4 N 4 were in good agreement with the experimental v…
Experimental and Theoretical Investigations of Structural Trends for Selenium(IV) Imides and Oxides: X-ray Structure of Se3(NAd) 2
The thermal decomposition of Se(NAd)(2) (Ad = 1-adamantyl) in THF was monitored by (77)Se NMR and shown to give the novel cyclic selenium imide Se(3)(NAd)(2) as one of the products. An X-ray structural determination showed that Se(3)(NAd)(2) is a puckered five-membered ring with d(Se-Se) = 2.404(1) A and |d(Se-N)| = 1.873(4) A. On the basis of (77)Se NMR data, other decomposition products include the six-membered ring Se(3)(NAd)(3), and the four-membered rings AdNSe(micro-NAd)(2)SeO and OSe(micro-NAd)(2)SeO. The energies for the cyclodimerization of E(NR)(2) and RNEO (E = S, Se; R = H, Me, (t)Bu, SiMe(3)), and the cycloaddition reactions of RNSeO with E(NR)(2), RNSO(2) with Se(NR)(2), and S…
Conformations and Energetics of Sulfur and Selenium Diimides
The geometries and energetics of different conformations of sulfur and selenium diimides E(NR) 2 (E = S, Se; R = H, Me, 'Bu, C 6 H 3 Me 2 -2,6, SiMe 3 ) have been studied by using various ab initio and DFT molecular orbital techniques. The syn,syn conformation is found to be most stable for parent E(NH) 2 , but in general, the preferred molecular conformation for substituted chalcogen diimides is syn,anti. In the case of E(NH) 2 the present calculations further confirm that syn,syn and syn,anti conformations lie energetically close to each other. From the three different theoretical methods used, B3PW91/6.31G * proved to be the most suitable method for predicting the geometries of chalcogen…
Bonding Trends in Lewis Acid Adducts of S4N4 — X-Ray Structure of TeCl4×S4N4.
Tetrasulfur tetranitride and tellurium tetrachloride react in dichloromethane to form a 1:1 adduct TeCl4·S4N4 (1). The crystal structure of 1 shows that TeCl4 is bonded to the S4N4 ring through a Te–N linkage. As a consequence, the transannular S···S bonds in S4N4 are broken and the molecule assumes an open, monocyclic conformation. The Te–N bond of 2.16(1) A is slightly longer than the single bond. The S–N bonds span a range of 1.55(1)–1.67(1) A. The adduct 1 was also characterized by mass spectrometry and Raman spectroscopy. The bonding and spectroscopic properties of 1 are compared by DFT calculations at the B3PW91/(RLC ECP) level of theory with those of BF3·S4N4 (2), SO3·S4N4 (3), AsF5·…
Ruthenium‐assisted tellurium abstraction in bis(thiophen‐2‐yl) ditelluride
The reaction of [RuCl2(CO)3]2 and Te2Tpn2 (Tpn = thiophen-2-yl, C4H3S) in the absence of light resulted in the formation of cct-[RuCl2(CO)2(TeTpn2)2] (1) [cis(Cl)-cis(CO)-trans(TeTpn2)] and TeTpn2 (2) together with the precipitation of tellurium. The complex 1 and the monotelluride 2 were characterized by NMR spectroscopy and single-crystal X-ray diffraction. The decomposition of Te2Tpn2 to TeTpn2 has been monitored by 125Te NMR spectroscopy and seemed to be faster than the ligand substitution in [RuCl2(CO)3]2 by TeTpn2. A catalytic cycle is proposed for the decomposition of Te2Tpn2 to TeTpn2 based on the PBE0-D3/def2-TZVP calculations. peerReviewed
Titanocene Selenide Sulfides Revisited: Formation, Stabilities, and NMR Spectroscopic Properties
[TiCp2S5] (phase A), [TiCp2Se5] (phase F), and five solid solutions of mixed titanocene selenide sulfides [TiCp2SexS5−x] (Cp = C5H5−) with the initial Se:S ranging from 1:4 to 4:1 (phases B–E) were prepared by reduction of elemental sulfur or selenium or their mixtures by lithium triethylhydridoborate in thf followed by the treatment with titanocene dichloride [TiCp2Cl2]. Their 77Se and 13C NMR spectra were recorded from the CS2 solution. The definite assignment of the 77Se NMR spectra was based on the PBE0/def2-TZVPP calculations of the 77Se chemical shifts and is supported by 13C NMR spectra of the samples. The following complexes in varying ratios were identified in the CS2 solutions of …
Front Cover: Chalcogen‐Bonding Interactions in Telluroether Heterocycles [Te(CH 2 ) m ] n ( n= 1–4; m= 3–7) (Chem. Eur. J. 61/2020)
Bonding Trends in Lewis Acid Adducts of S 4 N 4 – X‐ray Structure of TeCl 4 ·S 4 N 4
Tetrasulfur tetranitride and tellurium tetrachloride react in dichloromethane to form a 1:1 adduct TeCl4·S4N4 (1). The crystal structure of 1 shows that TeCl4 is bonded to the S4N4 ring through a Te–N linkage. As a consequence, the transannular S···S bonds in S4N4 are broken and the molecule assumes an open, monocyclic conformation. The Te–N bond of 2.16(1) A is slightly longer than the single bond. The S–N bonds span a range of 1.55(1)–1.67(1) A. The adduct 1 was also characterized by mass spectrometry and Raman spectroscopy. The bonding and spectroscopic properties of 1 are compared by DFT calculations at the B3PW91/(RLC ECP) level of theory with those of BF3·S4N4 (2), SO3·S4N4 (3), AsF5·…
Preparation and structural characterization of (Me(3)SiNSN)(2)Se, a new synthon for sulfur-selenium nitrides.
The reaction of (Me(3)SiN)(2)S with SeCl(2) (2:1 ratio) in CH(2)Cl(2) at -70 degrees C provides a route to the novel mixed selenium-sulfur-nitrogen compound (Me(3)SiNSN)(2)Se (1). Crystals of 1 are monoclinic and belong the space group P2(1)/c, with a = 7.236(1) A, b = 19.260(4) A, c = 11.436(2) A, beta = 92.05(3) degrees, V = 1592.7(5) A(3), Z = 4, and T = -155(2) degrees C. The NSNSeNSN chain in 1 consists of Se-N single bonds (1.844(3) A) and S=N double bonds (1.521(3)-1.548(3) A) with syn and anti geometry at the N=S=N units. The N-Se-N bond angle is 91.8(1) degrees. The EI mass spectrum shows a molecular ion with good agreement between the observed and calculated isotopic distributions…
Electronic Structures and Spectroscopic Properties of 6π-Electron Ring Molecules and Ions E2N2 and E42+ (E = S, Se, Te)
The electronic structures and molecular properties of square-planar 6π-electron ring molecules and ions E2N2 and E42+ (E = S, Se, Te) were studied using various ab initio methods and density functionals. All species were found to contain singlet diradical character in their electronic structures. Detailed analysis of the CAS wave function of S2N2 in terms of different valence bond structures gives the largest weight for a Lewis-type singlet diradical VB structure in which the two unpaired electrons reside on nitrogen atoms, though the relative importance of the different VB structures is highly dependent on the level of theory. The diradical character in both E2N2 and E42+ was found to incr…
Isomerism in [MCl2(ERR‘)2] (M = Pd, Pt; E = S, Se; R, R‘ = Me, Ph)
A series of thioether and selenoether complexes [MCl2(EPh2)2] and [MCl2(SMePh)2] (M = Pt, Pd; E = S, Se) have been prepared and characterized to explore the isomerism of the complexes in solution and in the solid state. The NMR spectroscopic information indicates that only one isomer is present in solution in case of the palladium complexes, while two isomers are formed in the case of most platinum complexes. Single-crystal X-ray structures of trans-[PdCl2(SPh2)2] (1t), trans-[PdCl2(SePh2)2] (2t), cis-[PtCl2(SePh2)2] (4c), trans-[PdCl2(SMePh)2] (5t), and trans-[PtCl2(SMePh)2] (7t) are reported and have been used as starting points for the X-ray powder diffraction structure determinations us…
Chalcogen‐Bonding Interactions in Telluroether Heterocycles [Te(CH2)m]n(n=1–4;m=3–7)
The Te⋅⋅⋅Te secondary bonding interactions (SBIs) in solid cyclic telluroethers were explored by preparing and structurally characterizing a series of [Te(CH2 )m ]n (n=1-4; m=3-7) species. The SBIs in 1,7-Te2 (CH2 )10 , 1,8-Te2 (CH2 )12 , 1,5,9-Te3 (CH2 )9 , 1,8,15-Te3 (CH2 )18 , 1,7,13,19-Te4 (CH2 )20 , 1,8,15,22-Te4 (CH2 )24 and 1,9,17,25-Te4 (CH2 )28 lead to tubular packing of the molecules, as has been observed previously for related thio- and selenoether rings. The nature of the intermolecular interactions was explored by solid-state PBE0-D3/pob-TZVP calculations involving periodic boundary conditions. The molecular packing in 1,7,13,19-Te4 (CH2 )20 , 1,8,15,22-Te4 (CH2 )24 and 1,9,17,…
"Identification of mixed bromidochloridotellurate anions in disordered crystal structures of (bdmim)2[TeX2Y4] (X, Y = Br, Cl; bdmim = 1-butyl-2,3-dimethylimidazolium) by combined application of Raman spectroscopy and solid-state DFT calculations"
Abstract The discrete mixed [TeBrxCl6−x]2− anions in their disordered crystal structures have been identified by using the phases prepared by the reaction of 1-butyl-2,3-dimethylimidazolium halogenides (bdmim)X with tellurium tetrahalogenides TeX4 (X = Cl, Br) as examples. Homoleptic (bdmim)2[TeX6] [X = Cl (1), Br (2)] and mixed (bdmim)2[TeBr2Cl4] (3), and (bdmim)2[TeBr4Cl2] (4) are formed depending on the choice of the reagents, and their crystal structures have been determined by single-crystal X-ray diffraction. The coordination environments of tellurium in all hexahalogenidotellurates are almost octahedral. Because of the crystallographic disorder, the mixed [TeBr2Cl4]2− and [TeBr4Cl2]2…
Formation, Structural Characterization, and Calculated NMR Chemical Shifts of Selenium-Nitrogen Compounds from SeCl4 and ArNHLi (Ar = supermesityl, mesityl)
Supermesityl selenium diimide [Se{N(C6H2tBu3-2, 4, 6)}2; Se{N(mes*)}2] can be prepared in a good yield from the reaction of SeCl4 and (mes*)NHLi. The molecule adopts an unprecedented anti, anti-conformation, as deduced by DFT calculations at PBE0/TZVP level of theory and supported by 77Se NMR spectroscopy and a crystal structure determination. An analogous reaction involving (C6H2Me3-2, 4, 6)NHLi [(mes)NHLi] unexpectedly lead to the reduction of selenium and afforded the selenium diamide Se{NH(mes)}2 that was characterized by X-ray crystallography and 77Se NMR spectroscopy. The Se-N bonds of 1.847(3) and 1.852(3) A show normal single bond lengths. The <NSeN bond angle of 109.9(1)° also indi…
An experimental and theoretical study of the isomerization of mononuclear bis(arylselenolato)bis(triphenylphosphine)platinum complexes [Pt(SeR)2(PPh3)2]
Abstract Mononuclear bis(thienylselenolato)bis(triphenylphosphine)platinum [Pt(SeTh)2(PPh3)2] (Th=2-thienyl, C4H3S) has been prepared by the treatment of cis-[PtCl2(PPh3)2] with NaSeTh. The 31P-NMR spectroscopic information indicates that cis-[Pt(SeTh)2(PPh3)2] is initially formed in the reaction. Upon prolonged standing in solution it isomerizes to trans-[Pt(SeTh)2(PPh3)2]. The reaction of cis-[PtCl2(PPh3)2] with LiSeFu (Fu=2-furyl, C4H3O) affords immediately a mixture of cis- and trans-isomers of [Pt(SeFu)2(PPh3)2] with the relative amount of the trans-isomer increasing with time. The recrystallization of the two reaction mixtures yielded cis,anti- and trans,syn-isomers of [Pt(SeTh)2(PPh3…
Halogenation of tellurium by SO2Cl2. Formation and crystal structures of (H3O)[Te3Cl13]·1/2SO2, [(C4H8O)2H][TeCl5]·(C4H8O), [(Me2SO)2H]2[TeCl6], and [Ni(NCCH3)6][Te2Cl10]
Abstract The halogenation of elemental tellurium with SO2Cl2 in various solvents has been investigated. (H3O)[Te3Cl13]·1/2SO2 (1) and [(C4H8O)2H][TeCl5]·(C4H8O) (2) were obtained in CS2 and THF, respectively. When DMSO is added into the THF solution of tellurium and SO2Cl2, [(Me2SO)2H]2[TeCl6] (3) is formed. In the acetonitrile solution tellurium and SO2Cl2 form [Ni(NCCH3)6][Te2Cl10] (4) in the presence of metallic nickel. All compounds 1–4 were characterized by 125Te NMR and by X-ray crystallography. The formation of the anions has been discussed.
Experimental and computational investigation on the formation pathway of [RuCl2(CO)2(ERR′)2] (E = S, Se, Te; R, R′ = Me, Ph) from [RuCl2(CO)3]2 and ERR′
The pathways to the formation of the series of [RuCl2(CO)2(ERR′)2] (E = S, Se, Te; R, R′ = Me, Ph) complexes from [RuCl2(CO)3]2 and ERR′ have been explored experimentally in THF and CH2Cl2, and computationally by PBE0-D3/def2-TZVP calculations. The end-products and some reaction intermediates have been isolated and identified by NMR spectroscopy, and their crystal structures have been determined by X-ray diffraction. The relative stabilities of the [RuCl2(CO)2(ERR′)2] isomers follow the order cct > ccc > tcc > ttt ≈ ctc (the terms c/t refer to cis/trans arrangement of the ligands in the order of Cl, CO, and ERR′). The yields were rather similar in both solvents, but the reactions were signi…
Selenium Imides: 77Se NMR Investigations of the SeCl2−tBuNH2 Reaction and X-ray Structures of Se3(NtBu)3, tBuNSe(μ-NtBu)2SO2, and tBuNSe(μ-NtBu)2SeO
The reaction of SeCl2 with tert-butylamine in various molar ratios in THF at −78 °C has been investigated by 77Se NMR spectroscopy. In addition to the known Se−N heterocycles Se6(NtBu)2 (1) and Se9(NtBu)6 (2), the acyclic imidoselenium(II) dichlorides ClSe[N(tBu)Se]nCl (4, n = 1; 5, n = 2) and two new cyclic selenium imides [Se3(NtBu)2]n (3, n = 1 or 2) and Se3(NtBu)3 (6) have been isolated and identified. An X-ray analysis shows that 6 is a six-membered ring in a chair conformation with |d(Se−N)| = 1.833 A. Crystal data: 6, trigonal, P3c1, a = 9.8660(3) A, c = 20.8427(7) A, V = 1757.0(1) A3, Z = 6. The 1H, 13C, and 77Se NMR data for 1−6 are reported, and some reassignments of earlier lite…
A Selenium-Nitrogen Chain with Selenium in Different Oxidation States
The reaction of tBuNH2 with a mixture of SeCl2 and SeOCl2 in a 6:2:1 molar ratio produces the novel selenium-nitrogen chain ClSeN(tBu)Se(O)Cl (4), in which the selenium atoms are in two different oxidation states, SeII and SeIV. The crystal structure of 4 is compared with that of the related SeII/SeII system ClSeN(tBu)SeCl (1) and differences are attributed to hyperconjugative effects. The energetics of the formation of 4 via two different routes are elucidated by PBE0/def2-TZVPP calculations. peerReviewed
A Selenium-Nitrogen Chain with Selenium in Different Oxidation States
ChemInform Abstract: Preparation and Structural Characterization of (Me3SiNSN)2Se, a New Synthon for Sulfur-Selenium Nitrides.
The reaction of (Me(3)SiN)(2)S with SeCl(2) (2:1 ratio) in CH(2)Cl(2) at -70 degrees C provides a route to the novel mixed selenium-sulfur-nitrogen compound (Me(3)SiNSN)(2)Se (1). Crystals of 1 are monoclinic and belong the space group P2(1)/c, with a = 7.236(1) A, b = 19.260(4) A, c = 11.436(2) A, beta = 92.05(3) degrees, V = 1592.7(5) A(3), Z = 4, and T = -155(2) degrees C. The NSNSeNSN chain in 1 consists of Se-N single bonds (1.844(3) A) and S=N double bonds (1.521(3)-1.548(3) A) with syn and anti geometry at the N=S=N units. The N-Se-N bond angle is 91.8(1) degrees. The EI mass spectrum shows a molecular ion with good agreement between the observed and calculated isotopic distributions…
CCDC 1887989: Experimental Crystal Structure Determination
Related Article: Heli Laasonen, Johanna Ikäheimonen, Mikko Suomela, J. Mikko Rautiainen, Risto S. Laitinen|2019|Molecules|24|319|doi:10.3390/molecules24020319
CCDC 2060504: Experimental Crystal Structure Determination
Related Article: Marjaana Taimisto, Merja J. Poropudas, J. Mikko Rautiainen, Raija Oilunkaniemi, Risto S. Laitinen|2023|Eur.J.Inorg.Chem.||e202200772|doi:10.1002/ejic.202200772
CCDC 1986246: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 1522803: Experimental Crystal Structure Determination
Related Article: Aino J. Karhu, Juho Jämsä, J. Mikko Rautiainen, Raija Oilunkaniemi, Tristram Chivers and Risto S. Laitinen|2017|Z.Anorg.Allg.Chem.|643|495|doi:10.1002/zaac.201700031
CCDC 1986247: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 929110: Experimental Crystal Structure Determination
Related Article: Sari M. Närhi, Johanna Kutuniva, Marja K. Lajunen, Manu K. Lahtinen, Heikki M. Tuononen, Antti J. Karttunen, Raija Oilunkaniemi, Risto S. Laitinen|2014|Spectrochim.Acta,Part A|117|728|doi:10.1016/j.saa.2013.09.063
CCDC 1887990: Experimental Crystal Structure Determination
Related Article: Heli Laasonen, Johanna Ikäheimonen, Mikko Suomela, J. Mikko Rautiainen, Risto S. Laitinen|2019|Molecules|24|319|doi:10.3390/molecules24020319
CCDC 929107: Experimental Crystal Structure Determination
Related Article: Sari M. Närhi, Johanna Kutuniva, Marja K. Lajunen, Manu K. Lahtinen, Heikki M. Tuononen, Antti J. Karttunen, Raija Oilunkaniemi, Risto S. Laitinen|2014|Spectrochim.Acta,Part A|117|728|doi:10.1016/j.saa.2013.09.063
CCDC 929106: Experimental Crystal Structure Determination
Related Article: Sari M. Närhi, Johanna Kutuniva, Marja K. Lajunen, Manu K. Lahtinen, Heikki M. Tuononen, Antti J. Karttunen, Raija Oilunkaniemi, Risto S. Laitinen|2014|Spectrochim.Acta,Part A|117|728|doi:10.1016/j.saa.2013.09.063
CCDC 2060503: Experimental Crystal Structure Determination
Related Article: Marjaana Taimisto, Merja J. Poropudas, J. Mikko Rautiainen, Raija Oilunkaniemi, Risto S. Laitinen|2023|Eur.J.Inorg.Chem.||e202200772|doi:10.1002/ejic.202200772
CCDC 1986249: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 1986248: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 1986251: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 1986252: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 1887988: Experimental Crystal Structure Determination
Related Article: Heli Laasonen, Johanna Ikäheimonen, Mikko Suomela, J. Mikko Rautiainen, Risto S. Laitinen|2019|Molecules|24|319|doi:10.3390/molecules24020319
CCDC 1986250: Experimental Crystal Structure Determination
Related Article: Marko Rodewald, J. Mikko Rautiainen, Tobias Niksch, Helmar Görls, Raija Oilunkaniemi, Wolfgang Weigand, Risto S. Laitinen|2020|Chem.-Eur.J.|26|13806|doi:10.1002/chem.202002510
CCDC 929108: Experimental Crystal Structure Determination
Related Article: Sari M. Närhi, Johanna Kutuniva, Marja K. Lajunen, Manu K. Lahtinen, Heikki M. Tuononen, Antti J. Karttunen, Raija Oilunkaniemi, Risto S. Laitinen|2014|Spectrochim.Acta,Part A|117|728|doi:10.1016/j.saa.2013.09.063
CCDC 929109: Experimental Crystal Structure Determination
Related Article: Sari M. Närhi, Johanna Kutuniva, Marja K. Lajunen, Manu K. Lahtinen, Heikki M. Tuononen, Antti J. Karttunen, Raija Oilunkaniemi, Risto S. Laitinen|2014|Spectrochim.Acta,Part A|117|728|doi:10.1016/j.saa.2013.09.063