Spectroscopy
- [NurdRage] Extracting Radioactive Salt from Chornobyl Blueberries
cross-posted from: https://sh.itjust.works/post/21614029
> One of the OG YouTube chemists dabbles in some radiochemistry and spectroscopy.
- Near-ultraviolet photon-counting dual-comb spectroscopy - Naturewww.nature.com Near-ultraviolet photon-counting dual-comb spectroscopy - Nature
We demonstrate a photon-counting approach that extends the unique advantages of spectroscopy with interfering frequency combs into regions where nonlinear frequency conversion tends to be very inefficient, providing a step towards precision broadband spectroscopy at short wavelengths and extrem...
- Observation of geometric phase effect through backward angular oscillations in the H + HD → H2 + D reaction - Nature Communicationswww.nature.com Observation of geometric phase effect through backward angular oscillations in the H + HD → H2 + D reaction - Nature Communications
In a combined experimental and theoretical study of the H + HD → H2 + D reaction at low collision energy (1.72 eV), the authors obtain detailed information on the quantum reaction dynamics surrounding a conical intersection.
- Ultrafast electronic relaxation pathways of the molecular photoswitch quadricyclane - Nature Chemistrywww.nature.com Ultrafast electronic relaxation pathways of the molecular photoswitch quadricyclane - Nature Chemistry
Light-induced ultrafast switching between the molecular isomers norbornadiene and quadricyclane can reversibly store and release a substantial amount of chemical energy. Two competing pathways have now been identified by which electronically excited quadricyclane molecules relax to the electronic gr...
- A two-frame movie of X-ray induced structural dynamics in single free nanoparticles
PDF Link: https://arxiv.org/pdf/2312.12548.pdf
- Orbital perspective on high-harmonic generation from solids - Nature Communicationswww.nature.com Orbital perspective on high-harmonic generation from solids - Nature Communications
Here the authors identify real-space contributions to the characteristics of high-harmonic generation in ReS2 and demonstrate the possibility of laser-controlled emission. They find that the spectrum is not just determined by the band structure, but also by the interference between HHG signals comin...
- Deuterium UV lamp
Deuterium UV lamp for my DIY absorption spectrometer.
Took this photo today and I thought it looked pretty cool, so I wanted to share!
- Direct observation of geometric-phase interference in dynamics around a conical intersection
Nature chemistry link: https://www.nature.com/articles/s41557-023-01300-3
- Field-linked resonances of polar molecules - Naturewww.nature.com Field-linked resonances of polar molecules - Nature
A type of universal scattering resonance between ultracold microwave-dressed polar molecules associated with field-linked tetramer bound states in the long-range potential well is observed, providing a general strategy for resonant scattering between ultracold polar molecules.
- Real-space subfemtosecond imaging of quantum electronic coherences in molecules - Nature Photonicswww.nature.com Real-space subfemtosecond imaging of quantum electronic coherences in molecules - Nature Photonics
By combining scanning tunnelling microscopy and attosecond technologies, the coherent electronic motion generated in molecules by carrier-envelope-phase-stable laser pulses is visualized at ångström-scale spatial resolution and subfemtosecond temporal resolution.
- Spectroscopy signatures of electron correlations in a trilayer graphene/hBN moiré superlattice
arXiv url: https://arxiv.org/pdf/2202.12330.pdf
- Sex type determination in papaya seeds and leaves using near infrared spectroscopy combined with multivariate techniques and machine learning
Papayas can be male, female, or hermaphrodite. Usually, papaya growers will select hermaphrodites because they can self-fertilize and thus produce fruit by themselves. However, this selection takes time an resources because the plants have to flower before the sex can determined.
The linked paper is a paper about combining machine learning and spectroscopy in order to determine the sex of a papaya by performing spectral measurements on the seed or leaves.
The spectral differences of the seeds suggest that hermaphrodite seeds have a slightly different lipid composition, but other than that there are no obvious spectral differences between different genders.
The trained machine learning algorithm is also able to discriminate between sexes by measuring the spectra of leaves, even though a careful analysis of the spectra reveals no obvious differences.
As a spectroscopist I would like to have a clear spectral signature that provides some fundamental understanding of the biology of plant sex types. But machine learning algorithms don't care about these superfluous details, as they can find significant patterns where we might see noise and chaos. It is too bad they can't communicate to us their insight!
- Detecting spins by their fluorescence with a microwave photon counterwww.nature.com Detecting spins by their fluorescence with a microwave photon counter - Nature
An ensemble of electron spins is detected by their microwave fluorescence using a superconducting single microwave photon counter, making single-spin electron spin resonance spectroscopy a possible future prospect.
