Introduction to Dissociation Spectroscopy

What is/are Dissociation Spectroscopy?

Dissociation Spectroscopy - A cryogenic 22-pole ion trap apparatus is used in combination with a table-top pulsed IR source to probe weakly bound CH+-He and CH+-He4 complexes by predissociation spectroscopy at 4 K. ^[1] The detected HAT reactivities of the [(TPA)FeO(X)]+/2+ complexes correlate with the Fe=O and FeO−H stretching vibrations of the reactants and the respective products as determined by infrared photodissociation spectroscopy. ^[2] Intriguing vibrational features of solvated protonated methanol between 2400-3800 cm-1 are recorded by infrared predissociation spectroscopy. ^[3] We demonstrate that low-resolution UV–vis laser photodissociation spectroscopy can be applied in situ to identify the deprotomers of three coumaric acids, trans-para-coumaric acid (CMA), trans-caffeic acid (CA), and trans-ferulic acid (FA), formed via electrospray. ^[4] Infrared spectra of Rh2O9+ are measured by infrared photodissociation spectroscopy in the rhodium-oxygen and O O stretching frequency region observed at 1254, 876 and 1536 cm−1. ^[5] Here, we report the application of an external cavity, continuous wave, mid-IR QCL to cryogenic ion vibrational predissociation spectroscopy to analyze a set of large organic molecules, organometallic complexes, and isotopically labeled compounds. ^[6] The boron-dinitrogen cation complexes B(NN)3+ and B2(NN)3,4+ are produced in the gas phase and are studied by infrared photodissociation spectroscopy in the N-N stretching vibrational frequency region. ^[7] Herein, we probe the microhydration structure of cationic pyrimidine (Pym), a common building block of DNA/RNA bases, by infrared photodissociation spectroscopy (IRPD) of mass-selected microhydrated clusters, $$\hbox {Pym}^{+}$$ - $$\hbox {W}_{n}$$ (W= $$\hbox {H}_{2}\hbox {O}$$ ), in the size range $$n=1$$ –3. ^[8] Deprotomer-selected action spectra are recorded over the S1 ← S0 band using an instrument with differential mobility spectrometry coupled with photodissociation spectroscopy. ^[9] These ions are mass selected in a reflectron time-of-flight spectrometer and studied with visible and UV laser fixed-frequency photodissociation and with tunable infrared laser photodissociation spectroscopy. ^[10] The ions were mass selected in a reflectron time-of-flight spectrometer and investigated with photodissociation spectroscopy in the IR and near-IR regions. ^[11] A pulsed infrared laser has been used to study the OH stretching vibration by vibrational predissociation spectroscopy in trapped GlyH+(He)n ( n = 1 to 3), and only small shifts of the center frequency have been observed. ^[12] Heteronuclear group 15 metal-iron carbonyl cluster complexes of AmFe(CO)n- (A = Sb, Bi; m, n = 2-3) were generated in the gas phase and studied by infrared photodissociation spectroscopy in the carbonyl stretching region. ^[13] The bond dissociation energies of these complexes were determined by mass spectrometry collision-induced dissociations and their structures were studied by density functional theory calculations and infrared photodissociation spectroscopy. ^[14] Infrared photodissociation spectroscopy in conjunction with quantum chemical calculations confirm that the n=10 complex is the coordination saturated ion where a Fe(CO)4 fragment is bonded with a Ca(CO)6 fragment through two side‐on bridging carbonyl ligands. ^[15] Here we investigate mass-selected hydrated monovalent vanadium ions, with a hydration shell ranging from 1 to 41 water molecules, by photodissociation spectroscopy. ^[16] Time-resolved luminescence spectroscopy (solid state), supported by transient photodissociation spectroscopy (gas phase), confirm a lifetime of some tens of µs for the respective triplet states, as well as the energetics of thermally activated delayed luminescence, both being essential parameters for application of these materials based on earth-abundant copper in photocatalysis and luminescent devices. ^[17] Laser photodissociation spectroscopy (3. ^[18] Vibrational assignments of 4MetFA and 4MetFA-W in the neutral (S0 and S1) and ionic (D0) electronic states measured by ns IR dip and electron-impact IR photodissociation spectroscopy are also discussed prior to the results of time-resolved spectroscopy. ^[19] In the present study, infrared photodissociation spectroscopy is applied to (H2O-Krn)+ (n = 1-3) radical cation clusters. ^[20] Vibrational modes of the relatively strongly bound H2He+ molecular ion and its deuterated congener D2He+ are investigated by low-resolution multi-photon photodissociation spectroscopy, using a combination of a 4 K cryogenic ion-trap machine and the free-electron-laser FELIX. ^[21] The use of gas-phase methods including mass spectrometry, ion mobility mass spectrometry, collision-induced dissociation mass spectrometry, photoelectron spectroscopy, and photodissociation spectroscopy will reveal novel and complementary information on their intrinsic geometric and electronic structures that cannot be obtained by conventional characterization methods. ^[22] Using anion photodissociation spectroscopy, we have measured the intrinsic absorption electronic spectroscopy (400–214 nm) and numerous accompanying ionic photofragmentation pathways of the benzophenone-4 anion ([BP4–H]−). ^[23] The relaxation dynamics of protonated keto uracil has been investigated through cryogenic UV photodissociation spectroscopy. ^[24] Herein, we employ vibronic photodissociation spectroscopy of cryogenic M+LF complexes composed of lumiflavin (LF, C13H12N4O2), the parent molecule of the flavin family, and alkali ions (M = Li-Cs) to characterize the strong impact of metalation on the electronic properties of the LF chromophore. ^[25] Here, we give an overview of the most popular variants of infrared action spectroscopy and describe the advantages of using cryogenic ion traps in combination with messenger tagging and vibrational predissociation spectroscopy. ^[26] The octacarbonyl cation and anion complexes of actinide metals [An(CO)8]+/− (An=Th, U) are prepared in the gas phase and are studied by mass‐selected infrared photodissociation spectroscopy. ^[27] A cryogenic cylindrical ion trap velocity map imaging spectrometer has been developed to study photodissociation spectroscopy and dynamics of gaseous molecular ions and ionic complexes. ^[28] Electronic absorption spectra of water cluster anions (H2O)n–, n ≤ 200, at T = 80 K are obtained by photodissociation spectroscopy and compared with simulations from literature and experimental data for bulk hydrated electrons. ^[29] Infrared Photodissociation Spectroscopy (IRPD) showed that cysteine binds to the ruthenium atoms via the deprotonated thiol group and that sulfur bridges the ruthenium centers. ^[30] In order to derive precise predictions for the rotational states, the high resolution infrared predissociation spectroscopy of the v1 C-H stretching mode is revisited. ^[31] Electronic spectra of mass-selected HC4H2+-Arn (n=1-3) and HC4H2+-(N2)n (n=1-2) complexes are measured over the 290-530 nm range using resonance-enhanced photodissociation spectroscopy in a tandem mass spectrometer. ^[32] Vibrational spectra of the mass-selected ions tagged with Ne were recorded using infrared predissociation spectroscopy in a cryogenic ion trap instrument using the intense and widely tunable radiation of a free electron laser. ^[33] Complexes of the form V+(C2H2)n were produced in the gas phase via laser ablation in a pulsed-nozzle source, size-selected with a mass spectrometer, and studied with infrared laser photodissociation spectroscopy. ^[34] From 2003 to 2017, his scientific interests shifted to more structural questions, notably to resolving the structures and binding motifs of metal ion chelation complexes by application of infrared photodissociation spectroscopy. ^[35] To investigate the isomerization of ionized ethylene glycol, the infrared predissociation spectroscopy based on the vacuum ultraviolet photoionization is carried out for neutral and cationic ethylene glycol and partially deuterated isotopomer (HOCD2CD2OH). ^[36] We then explored the structural motifs of these H-bonded configurations at the molecular level by analyzing the cryogenic ion vibrational predissociation spectroscopy of cold (∼35 K) gas phase cluster ions with quantum chemical methods. ^[37] With the emergence of ion-mobility techniques combined with tuneable-laser photodissociation spectroscopy, new experimental combinations are possible to now meet this challenge. ^[38] We also used orthogonal methods, such as quantum chemistry, ion mobility spectrometry and infrared photodissociation spectroscopy to establish the structures of the fragment ions. ^[39] The protonated species is subsequently probed using infrared photodissociation spectroscopy, and following a comparison with calculations, we identify the two isomers whose roles in Fischer esterification are debated. ^[40] Gaseous TMO(CO)n+ (TM = Sc, Y, La) complex cations prepared via laser vaporization were mass-selected and studied by infrared photodissociation spectroscopy in the C-O stretching frequency region. ^[41] We investigate the gaseous ScO(H2O)1-3Ar+ cations prepared by laser vaporization coupled with supersonic molecular beam using infrared photodissociation spectroscopy in the O-H stretching region. ^[42] Here, we use gas-phase laser photodissociation spectroscopy for the first time to measure the intrinsic UVA-UVC absorption spectra and associated photodegradation products of protonated and deprotonated oxybenzone, away from the complications of bulk mixtures. ^[43] UV photodissociation spectroscopy is performed to obtain the UV spectra of the complexes. ^[44] This study reveals important new isomers and isomerization pathways on the C7H8+ potential energy surface, through the application of gas-phase electronic photodissociation spectroscopy in conjunction with ab initio calculations. ^[45] The nature of electronic transitions is authenticated by absorption and photodissociation spectroscopy in parallel with high-level quantum chemical computations utilizing the GW method and Bethe-Salpeter equation (GW-BSE). ^[46] The spontaneous radiative cooling of the prototype interstellar molecule CH+ to its lowest rotational states has been demonstrated by photodissociation spectroscopy, paving the way for experiments under true interstellar conditions. ^[47] We fill this gap by elucidating the structure of cationic copper clusters through infrared (IR) photodissociation spectroscopy of Cun+–Arm complexes. ^[48] Structures of all intermediates were fully characterised by isotopic labelling and by photodissociation spectroscopy. ^[49] The ions are mass selected and studied via infrared laser photodissociation spectroscopy in the C H stretching region (2600–3400 cm−1). ^[50]

mass selected infrared

The infrared spectra were measured via mass-selected infrared photodissociation spectroscopy of their CO-tagged complexes [H n C4O·CO]+ (n = 1, 2). ^[1] Heteronuclear BeFe(CO) 4 - anion complex is generated in the gas phase, which is detected by mass-selected infrared photodissociation spectroscopy in the carbonyl stretching frequency region. ^[2] Their infrared spectra are measured via mass-selected infrared photodissociation spectroscopy of the CO “tagged” [HC2nO·CO]+ cation complexes in 1600–3500 cm−1 frequency range. ^[3] Heteronuclear transition-metal-main-group element carbonyl anion complexes of AFe(CO)3- (A = Ge, Sn, and Pb) are prepared using a laser vaporization supersonic ion source in the gas phase, which were studied by mass-selected infrared (IR) photodissociation spectroscopy. ^[4] Here we report that main group element boron is able to form quadruple bonding interactions with iron in the BFe(CO)3 - anion complex, which has been revealed by quantum chemical investigation and identified by mass-selected infrared photodissociation spectroscopy in the gas phase. ^[5] Heteronuclear group-3 metal-iron carbonyl anion complexes ScFe(CO)3-, YFe(CO)3-, and LaFe(CO)3- are prepared in the gas phase and are studied by mass-selected infrared (IR) photodissociation spectroscopy as well as quantum chemical calculations. ^[6] The lanthanide octacarbonyl anion complexes Ln(CO)8 - (Ln=Tm, Yb, Lu) were produced in the gas phase and detected by mass-selected infrared photodissociation spectroscopy in the carbonyl stretching-frequency region. ^[7] The alkali metal-nickel carbonyl anions ENi(CO)3 - with E=Li, Na, K, Rb, Cs have been produced and characterized by mass-selected infrared photodissociation spectroscopy in the gas phase. ^[8]

infrared multiple photon

The infrared spectra of CO3 •-(H2O)1,2 and CO4 •-(H2O)1,2 were measured via infrared multiple photon dissociation spectroscopy in both warm and cold environments. ^[1] Infrared multiple photon dissociation spectroscopy, ion-molecule reaction experiments, and theoretical calculations have been used to investigate the structures of these ions. ^[2] Because the shift in ν3 is predicted to be most dramatic when X = F, we revisited these species using infrared multiple-photon photodissociation spectroscopy. ^[3] The interaction of hydrogen with doubly vanadium doped aluminum clusters, AlnV2+ (n = 1–12), is studied experimentally by time-of-flight mass spectrometry and infrared multiple photon dissociation spectroscopy. ^[4] The CO adsorption is studied by combining low-pressure collision cell reactivity and infrared multiple photon dissociation spectroscopy experiments with density functional theory calculations. ^[5] The regiospecifically formed N• species were characterized by infrared multiple-photon dissociation spectroscopy which revealed that the WA tryptophan-N• radical remains the nitrogen radical, while the AW nitrogen radical rearranges into the π-radical cation. ^[6] The gas-phase structure of protonated β-methylaminoalanine was investigated using infrared multiple photon dissociation spectroscopy in the C–H, N–H, O–H stretching region (2700–3800 cm−1) and the fingerprint region (1000–1900 cm−1). ^[7] We therefore used infrared multiple-photon photodissociation spectroscopy to determine the structures of both [ZnNO3(CH3OH)2]+ and [ZnNO3(CH3OH)]+. ^[8]

Photon Dissociation Spectroscopy

The infrared spectra of CO3 •-(H2O)1,2 and CO4 •-(H2O)1,2 were measured via infrared multiple photon dissociation spectroscopy in both warm and cold environments. ^[1] The bare deprotonated form of pantothenic acid, [panto-H]−, its complex with Ca(II) ion, [Ca(panto-H)]+, and singly charged micro-hydrated calcium pantothenate [Ca(panto-H)(H2O)]+ adduct have been obtained in the gas phase by electrospray ionization and assayed by mass spectrometry and IR multiple photon dissociation spectroscopy in the fingerprint spectral range. ^[2] Infrared multiple photon dissociation spectroscopy, ion-molecule reaction experiments, and theoretical calculations have been used to investigate the structures of these ions. ^[3] The interaction of hydrogen with doubly vanadium doped aluminum clusters, AlnV2+ (n = 1–12), is studied experimentally by time-of-flight mass spectrometry and infrared multiple photon dissociation spectroscopy. ^[4] The CO adsorption is studied by combining low-pressure collision cell reactivity and infrared multiple photon dissociation spectroscopy experiments with density functional theory calculations. ^[5] Vibrationally resolved photofragment excitation spectra are recorded for individual isotopologues of Br2+ (79Br2+, 79Br81Br+, 81Br2+) by [1+1] two-photon dissociation spectroscopy. ^[6] The regiospecifically formed N• species were characterized by infrared multiple-photon dissociation spectroscopy which revealed that the WA tryptophan-N• radical remains the nitrogen radical, while the AW nitrogen radical rearranges into the π-radical cation. ^[7] The gas-phase structure of protonated β-methylaminoalanine was investigated using infrared multiple photon dissociation spectroscopy in the C–H, N–H, O–H stretching region (2700–3800 cm−1) and the fingerprint region (1000–1900 cm−1). ^[8]