Sum-frequency generation vibrational spectroscopy (SFG-VS) can provide detailed information and understanding of the molecular composition, interactions, orientational conformational structure surfaces interfaces through quantitative measurement analysis. In this review, we present current status discuss important recent developments in intrinsic SFG spectral lineshapes formulations for polarization measurements analysis SFG-VS spectra. The focus review is to a coherent description main...

The ability to achieve sub-wavenumber resolution (0.6 cm−1) and a large signal-to-noise ratio in high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS) allows for the detailed SFG spectral lineshapes be used unambiguous determination of fine features. Changes structural spectroscopic phase SFG-VS as function beam polarization experimental geometry proved instrumental identification an unexpected 2.78 ± 0.07 cm−1 splitting two methyl groups at...

The lack of understanding the temporal effects and restricted ability to control experimental conditions in order obtain intrinsic spectral lineshapes surface sum-frequency generation vibrational spectroscopy (SFG-VS) have limited its applications interfacial studies. emergence high-resolution broadband (HR-BB-SFG-VS) with sub-wavenumber resolution [Velarde et al., J. Chem. Phys., 2011, 135, 241102] offers new opportunities for obtaining SFG-VS. Particularly, high accuracy HR-BB-SFG-VS...

Small S–T splitting: The photoelectron spectrum of the oxyallyl radical anion (see picture) reveals that electronic ground state is singlet, and lowest triplet separated from singlet by only (55±2) meV in adiabatic energy. Oxyallyls are reactive intermediates, whose participation has been postulated ring opening cyclopropanones1 allene oxides,2 Favorskii rearrangement,3 a variety synthetically useful transformations.4 parent (OXA) can be viewed as derivative trimethylenemethane (TMM), which...

Substantial progress has been made in the quantitative understanding and interpretation of hydrogen bonding ordering structure air/water interface since first sum-frequency generation vibrational spectroscopy (SFG-VS) measurement by Q. Du et al. 1993 (Phys. Rev. Lett.1993, 70, 2312−2316). However, there are still disagreements controversies on consistency between different experimental measurements, as well theoretical computational results. One critical problem lies lack SFG-VS intensity...

Understanding the role of water in biological processes remains a central challenge life sciences. Water structures hydration shells biomolecules are difficult to study situ due overwhelming background from aqueous environments. Biological interfaces introduce additional complexity because biomolecular differs at compared bulk solution. Here, we perform experimental and computational studies chiral sum frequency generation (chiral SFG) spectroscopy probe chirality transfer protein...

While in principle the frequency-domain and time-domain spectroscopic measurements should generate identical information for a given molecular system, inhomogeneous character of surface vibrations sum-frequency generation vibrational spectroscopy (SFG-VS) studies has only been studied with SFG-VS by mapping decay polarization using ultrafast lasers, this due to lack SFG spectra high enough spectral resolution accurate lineshape. Here, recently developed high-resolution broadband...

Carboxylic acid is a common ligand anchoring group used to functionalize nanoparticle surfaces. Its binding structure and mechanism as function of the oxidation states metal oxide surfaces are not well characterized. Here we present an in situ sum-frequency generation vibrational spectroscopy (SFG-VS) spin-polarized density functional theory (DFT) study on deuterated acetic ceria nanoparticles (CNPs) aqueous solution. SFG spectra from CNP surface revealed that modes carboxylate depend cerium...

Despite the importance of terpenes in biology, environment, and catalysis, their vibrational spectra remain unassigned. Here, we present subwavenumber high-resolution broad-band sum frequency generation (HR-BB-SFG) common terpene (+)-α-pinene that reveal 10 peaks C-H stretching region at room temperature. The high spectral resolution resulted with more better resolved features than those Fourier transform infrared, femtosecond stimulated Raman bulk condensed phase conventional BB-SFG...

Abstract The creation of next‐generation flexible and conformable magneto‐optic (MO) materials with dramatically enhanced Verdet constant will significantly advance technologies, including optical isolation, magnetic quantum spin fluctuation measurements, cold atom coherence probes, while opening new possibilities for mapping weakly emanating fields from sources, microelectronics or brain activity. results presented here show that the natural coupling electric dipoles in a chiral polymer...

ABSTRACT Elucidating the crystalline‐amorphous interface during decrystallization processes in semi‐crystalline polyethylene (PE) is crucial for advancement of polymer theory and plastic‐to‐plastic recycling technologies. In this study, we carried out an in‐depth investigation PE thin films undergoing melting or dissolution using a temperature‐controlled liquid flow‐cell experimental setup which provided situ mid‐infrared (MIR, 4000–700 cm −1 ) near‐infrared (NIR, 6000–4000 spectra real...

The photoelectron spectrum of the oxyallyl (OXA) radical anion has been measured. generated in reaction atomic oxygen (O•−) with acetone. Three low-lying electronic states OXA have observed spectrum. Electronic structure calculations performed for triplet (3B2 and 3B1) ground doublet state (2A2) using density functional theory (DFT). Spectral simulations carried out based on results DFT calculations. simulation identifies a vibrational progression CCC bending mode 3B2 lower electron binding...

Doubly-resonant sum frequency generation (DR-SFG) spectra of fullerene thin films on metallic and dielectric substrates show modal substrate selectivity.

Machine learning of the mid-infrared spectra postconsumer plastics will help prevent, separate, and purify wastestreams contributing to global pollution.

Experimental methods capable of selectively probing water at the DNA minor groove, major and phosphate backbone are crucial for understanding how hydration influences structure function. Chiral-selective sum frequency generation spectroscopy (chiral SFG) is unique among vibrational spectroscopies because it can probe molecules that form chiral structures around biomolecules. However, interpreting SFG spectra challenging since both biomolecule produce signals. Here, we combine experiment...

The mass-selected [(CO(2))(2)(H(2)O)(m)](-) cluster anions are studied using a combination of photoelectron imaging and photofragment mass spectroscopy at 355 nm. Photoelectron studies carried out on the parent in m=2-6 size range; photofragmentation results presented for m=3-11. While images suggest possible coexistence CO(2) (-)(H(2)O)(m)CO(2) (O(2)CCO(2))(-)(H(2)O)(m) structures, particularly m=2 3, only (-) based clusters both required sufficient to explain all fragmentation pathways...

Nanosecond optical pulses with high power and spectral brightness in the deep ultraviolet (UV) region have been produced by sum frequency mixing of nearly transform-limited-bandwidth IR light originating from a home-built injection-seeded ring cavity KTiOPO4 parametric oscillator (OPO) fourth harmonic beam an Nd:YAG laser used simultaneously to pump OPO second harmonic. We demonstrate UV output, tunable 204 207 nm, which exhibits pulse energies up 5 mJ bandwidth better than 0.01 cm−1....

We report the first direct measurement of kinetic energy exoelectrons produced by collisions vibrationally excited molecules with a low work function metal surface exhibiting electron excitations 64% (most probable) and 95% (maximum) initial vibrational energy. This remarkable efficiency for vibrational-to-electronic transfer is in good agreement previous results suggesting coupling multiple quanta to single electron.

The C−H bond dissociation energies of closed-shell molecules decrease with increasing stability the resulting radicals. From electron affinity dicyanomethyl radical, •CH(CN)2, EA[•CH(CN)2] = 2.88 ± 0.01 eV, measured by photoelectron imaging CH(CN)2− anion, and acidity/electron thermodynamic cycle, we obtained enthalpy malononitrile, CH2(CN)2, DH298[H−CH(CN)2] 87 2 kcal/mol. This result is compared to corresponding value for acetonitrile, DH298(H−CH2CN) 93 kcal/mol, determined from a similar...

Polarization sum frequency generation vibrational spectra (SFG-VS) reveals that there are two distinctively different but closely overlapping −CN vibrations at 2244.5 and 2251.1 cm–1, respectively, in the Langmuir monolayer of long-chain nonadecanenitrile (CH3(CH2)17CN, or C18CN) air/water interface. The blue-shifted group cm–1 peak is about 1.8 times broader than cm–1. Both spectral shift width consistent with picture this corresponds to solvated group, while signature less group....

The molecular self-assembly of surfactants on the surface single-walled carbon nanotubes (SWCNT) is currently a common strategy for tuning nanotube properties and stabilization dispersions. Here, we report direct measurements degree interfacial ordering sodium dodecyl sulfate (SDS) adsorbed colloidal, single-chirality enriched, SWCNTs within solid film investigate dependence alkyl chain order surfactant concentration in precursor solution. SWCNT-bound SDS molecules, probed by vibrational sum...

Photoelectron images are recorded in the photodetachment of two series cluster anions, (CO(2))(n)(-), n=4-9 and (CO(2))(n)(-).H(2)O, n=2-7, with linearly polarized 400 nm light. The energetics observed bands compare well previous studies, showing evidence for switching between anionic core structures: CO(2)(-) monomer covalent (CO(2))(2)(-) dimer anions. systematic study photoelectron angular distributions (PADs) sheds light on electronic structure different anions indicates that solvation...

Electronic structure of the oxyallyl diradical and anion is investigated using high-level ab initio methods. Converged theoretical estimates energy differences between low-lying electronic states (OXA) as well detachment energies are reported. Our best adiabatic 2A2 neutral 3B2 3B1 1.94 2.73 eV, respectively. The 1A1 state lies above vertically, but geometric relaxation brings it below triplet. two-dimensional scan singlet potential surface (PES) reveals that there no minimum corresponding...