UCSD Chem Biochem

Haiwang Yong lives in the ultrafast lane. He uses #UltrafastSpectroscopy to observe the motion of atoms and electrons in femtoseconds. Last year, Yong received an @ENERGY award and a grant from the W.M. Keck Foundation to support his work. bit.ly/4seZLlu @UCSDChemBiochem

🚨 New paper out in @JPhysChem Lett.! 🚨 We're excited to share our latest work (a collaboration with @BonnMischa's group at @mpi_polymer): 👉 pubs.acs.org/doi/10.1021/ac… At the #air/#water interface, "free" (dangling) O–H groups are responsible for a sharp peak at ~3700 cm⁻¹ in the vibrational sum-frequency generation (#vSFG) spectrum.⚡️ Because it’s so narrow, it’s often treated as spectrally #homogeneous. But is it really? 🌊 In this study, we combine: ✅ Three distinct polarization‑resolved heterodyne‑detected #vSFG measurements, reporting the first #SPS spectrum. ✅ Our #datadriven #manybody MB-pol potential for predictive simulations. ✅ Path‑integral-based quantum dynamics (Te‑PIGS) simulations to capture #NuclearQuantumEffects. Our key findings: 🎯 The free O–H peak shifts with polarization by ~13–15 cm⁻¹ → direct evidence that *orientation matters* even for “free” O–H. 🎯 Free O–H bonds tilted toward the interfacial plane are systematically red‑shifted compared to more upright O–H. 🎯 Mechanism: orientation‑dependent *local electric fields* from neighboring water molecules. Stronger projected fields along the O–H axis correlate with lower (red‑shifted) fundamental frequencies. Take‑home message: 🔎 A sharp peak ≠ a uniform interface. The #water surface is intrinsically heterogeneous, and polarization‑resolved spectroscopy + quantum many‑body simulations can read out that heterogeneity in terms of local electric fields. Huge congrats to #Richa for leading this project! 🙌 🙏 Big thanks to @NSF for funding and to @ACCESSforCI and @NERSC for providing computational resources! @UCSanDiego @UCSDPhySci @UCSDChemBiochem @HDSIUCSD @SDSC_UCSD

Congrats to UC San Diego's newest Sloan Research Fellows, including @Mattia__Serra and Fleur Ferguson. The fellowships acknowledge researchers whose innovation and research accomplishments set them apart as the next generation of leaders. bit.ly/4rgWsK8 @SloanFoundation

Huge congratulations to Prof. Shaowei Li and team on their @ScienceMagazine paper! 🎉 Single-molecule infrared spectroscopy with STM captures vibrational modes with atomic precision, opening a new era in bond-specific chemistry. @UCSanDiego @UCSDPhySci science.org/eprint/INVDJBZ…

🚨 New paper out in @JPhysChem Lett.! 🚨 We are excited to share our latest work: 👉 pubs.acs.org/doi/10.1021/ac… Interfacial #water behaves very differently from bulk #water. 🌊 At charged interfaces, interpreting vibrational sum-frequency generation (#vSFG) spectra becomes particularly challenging. ⚡️ The key question is: 🤔 What is truly “surface-specific” (χ²), and what originates from bulk field-induced contributions (χ³)? In this study, we combine: ✅ Our #datadriven #manybody MB-pol potential ✅ Temperature-elevated path-integral coarse-graining (Te-PIGS) to include #NuclearQuantumEffects ✅ Layer-resolved heterodyne-detected #vSFG simulations to provide a molecular-level separation of χ² and χ³ contributions at charged graphene oxide/water (#GO/#water) interfaces Our findings: 🎯 The prominent ~3200 cm⁻¹ band observed experimentally is not primarily surface-specific. It is dominated by field-induced bulk χ³ mixing associated with the electrical double layer. 🎯 In contrast, the strictly interfacial structure is encoded in χ². 🎯 This explicit χ²/χ³ decomposition clarifies how surface and bulk responses combine to shape measured #vSFG spectra at charged aqueous interfaces. Beyond #GO, this framework provides a general strategy to interpret vibrational spectra at charged and nanoconfined aqueous interfaces, with implications for: • Membrane science • Electrochemical systems • Sensing platforms • Interfacial reactivity Congratulations to #Toheeb and #Richa for leading this exciting collaboration between our groups at @UCSanDiego and @LSU! 🙌 Excited to see how heterodyne #vSFG experiments will further test these predictions. 🚀 @UCSDPhySci @UCSDChemBiochem @HDSIUCSD @SDSC_UCSD @LSU_Chemistry

Congratulations!

🔋 New work from @KentJGriffith reveals lithium and sodium intercalation with multielectron redox in vacancy-ordered and vacancy-disordered cation-deficient materials, advancing our understanding of next-generation electrodes. @UCSanDiego @UCSDPhySci pubs.acs.org/doi/10.1021/ja…

.@UCSDChemBiochem's Wei Wang has mapped the genetic programs that determine the behavior of powerful white blood cells, called CD8 killer T cells, which are critical for controlling infections and fighting cancer. This work appears in @Nature. bit.ly/4tnQyZo

#GeneTherapy holds the promise of curing disease, but to work the new gene must make it into a cell’s nucleus—a difficult task. Neal Devaraj’s lab at @UCSDChemBiochem presents a method that raises gene delivery efficacy while minimizing side effects. bit.ly/4r8GkKU

🔋@Tech_Networks quotes Prof. Kent Griffith on why low-field solid-state NMR with fast spinning is ideal for paramagnetic battery materials and enables measurements that high-field methods struggle to access. 🔬⚡ @UCSanDiego @UCSDPhySci technologynetworks.com/applied-scienc…

In this recently published @JPhysChem study led by @SindhanaPS with our collaborators (Giebink, Movassaghi, Nelson), we explain when chemical reactions can be modified by infrared excitation pubs.acs.org/doi/10.1021/ac…

Join UC San Diego's @UCSDChemBiochem on Feb. 25 for a virtual coffee chat showcasing the breadth and impact of our research. From atmospheric chemistry to quantum science and everything in between--we do it all! Register today: bit.ly/3ZtBsUt

From @MikeBurkartUCSD: “While all man-made objects have an impact on the planet, our goal is to minimize the ecological and health hazards of these now ubiquitous materials.” @UCSDChemBiochem

Our annual Kent Wilson lecture was given by Keith Nelson @ChemistryMIT. Keith discussed his common interests with the late Wilson and how dreams of coherent control of condensed matter have become true with the years. Very inspiring lecture and visit @UCSDChemBiochem @UCSDPhySci

✨ New @J_A_C_S from @AndrewBPun! Bulky molecular designs activate solid-state photon #upconversion, efficiently combining low-energy light into higher-energy emission. Light manipulation at its best! ⚡️ 👉 pubs.acs.org/doi/10.1021/ja… @UCSanDiego @UCSDPhySci

What an inspiring story! We are so proud of Cianna and her journey!

✨ New @J_A_C_S paper from @AlinaMSchimpf group: single-crystal-to-single-crystal (#SCSC) transformations give atomic-level control—#POM networks with up to 3 cations precisely placed. Atomic precision, unlocked! 🎯 pubs.acs.org/doi/abs/10.102… @UCSanDiego @UCSDPhySci

💡 New @J_A_C_S from the Romero Group (@R2G_UCSD): visible light drives “cut-and-paste” functional-group transposition in chalcones (against thermodynamics!) to reach transposed 1,2-diaryl enones. Uphill chemistry, made easy. 😎 @UCSanDiego @UCSDPhySci pubs.acs.org/doi/10.1021/ja…

Distinguished Professor Kim Prather (@kprather88) testified before the CA Senate on new #TijuanaRiver evidence: airborne toxics impacting #SouthBay communities. 🫧 Proud of her team for elevating this crisis statewide. 🚨 Watch: nbcsandiego.com/video/videos/s… @UCSanDiego @UCSDPhySci

.@KomorLab is at the cutting edge of curing #GeneticDisorders. Her team is working to develop the most precise, efficient base-editing tools. And none of it would be possible without federal research funding. bit.ly/4p2RaRw #FundScience @UCSDChemBiochem