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Abstract Autonomous experimentation–or self-driving labs–offers a systematic approach to accelerate materials discovery by integrating automated synthesis, characterization, and data-driven decision-making. We present a closed-loop workflow for the on-demand synthesis and structural characterization of colloidal gold nanoparticles, enabling direct mapping from composition to nanoscale structure. Our framework leverages differentiable models of spectral shape to address two central tasks in self-driving labs: (a) phase mapping, or identifying compositional regions with distinct structural behavior; and (b) material retrosynthesis, or optimizing compositions for target structure. Using functional data analysis, we develop a data-driven model with generative pre-training, active learning, and high-throughput experiments to predict spectral responses across composition space. We demonstrate the approach on seed-mediated growth of gold nanoparticles, showcasing its ability to extract design rules, reveal secondary interactions, and efficiently navigate morphology space. Gradient-based optimization of the models enables inverse design, making this a unified platform. 

Scanning tunneling microscopy (STM) offers unparalleled sub-molecular resolution for visualizing surface-bound molecular assemblies. We developed a custom 3D-printed liquid cell that enabled stable, long-duration liquid-phase STM imaging of a metallocene dimer assembled on a highly oriented pyrolytic graphite (HOPG) substrate. High-resolution images revealed two distinct molecular packing structures. However, STM alone is difficult to pinpoint the detailed molecular arrangements, resonance Raman spectroscopy (RRS) was used to provide complementary information. Aided with density functional theory (DFT) calculated RRS, a cis conformer of the metallocene dimer was identified as the more probable form in both crystal and surface-bound states. These findings led to assemblies with cyclopentadienyl rings pointing towards the HOPG, and the carbonyl groups towards the water. This work demonstrates the synergistic power of integrating STM, RRS, and DFT in elucidating molecular assembling structures at the solid–liquid interface. 

We explore the relative roles of Earth’s axial tilt (‘tilt effect’) and orbital eccentricity (‘distance effect’) on the seasonal cycle of tropical sea surface temperature (SST), decomposing the two contributions using simulations of an Earth System model varying eccentricity and longitude of perihelion.  This dataset archives model output produced in this investigation using the Community Earth System Model version 2, and MATLAB code for analyzing the data. 

We explore the relative roles of Earth’s axial tilt (‘tilt effect’) and orbital eccentricity (‘distance effect’) in generating the seasonal cycle of tropical sea surface temperature (SST), decomposing the two contributions using simulations of an Earth System model varying eccentricity and longitude of perihelion. Tropical SST seasonality is largely explained by the annual contribution from tilt, but with significant contributions from the semiannual contribution from tilt and annual contribution from distance, especially in regions where the tilt annual contribution is relatively small. Precessional changes to tropical SST seasonality are readily explained by the distance annual component whose amplitude increases linearly with eccentricity and whose phase changes linearly with the longitude of perihelion, while the tilt contributions remain essentially unchanged. As such, the annual cycle contribution from distance can become significant at high eccentricity (e > 0.05) and dominate the SST annual cycle in some regions of the Tropics. The annual cycle tropical SST response to the distance effect consists of a tropics-wide warming peaking ∼2 months after perihelion consistent with a direct thermodynamic effect, and a dynamic contribution characterized by a cooling of the Pacific cold tongue peaking 5-6 months after perihelion. For current orbital conditions, the thermodynamic contribution acts to dampen the tropical SST seasonal cycle of the northern hemisphere from the tilt influence and amplify it in the southern hemisphere. The dynamic contribution acts to shift the Pacific cold tongue seasonal cycle arising from tilt to earlier in the season, by ∼1 month.