Organic photovoltaics (OPVs) hold promise as a technology for low-cost, large-area power conversion. [1][2][3][4] Though conceptually straightforward, the processes required for effi cient operation of an organic solar cell -photon absorption and exciton (electron-hole pair) formation, dissociation of the exciton into separated charges, and collection of the charges -are inherently complex due to the characteristics of the π -conjugated organic materials, i.e., weak van der Waals intermolecular interactions, low dielectric constants, strong electron-electron interactions, and large electron-vibration couplings. The effective separation of the electron-hole pair requires that the active layer consist of two components, an electron-rich (hole-transport) donor material and an electron-defi cient (electron-transport) acceptor material. [ 5 ] This condition leads to a key bottleneck, both in terms of operation and basic understanding, as there exists a delicate interplay between charge-separation and (geminate and non-geminate) charge-recombination processes at the interface between the donor and acceptor materials.While the importance of the donor-acceptor interface has long been recognized, recent experimental evidence has shone new light on the morphological complexity; this is particularly the case in polymer-fullerene bulk-heterojunction (BHJ) solar cells, [ 6 , 7 ] and more recently in molecule-molecule and polymermolecule bilayers. [ 8 , 9 ] In addition to the possible miscibility of the two components, the deposition protocol (e.g., chemical vapor deposition, solution casting, or spin coating to name a few [ 2 , 10 ] ) and post-processing procedures (e.g., removal of solvent additives or solvent and thermal annealing [ 11 , 12 ] ) can impact the interface morphology. This morphological variability leads to diffi culties, then, in recognizing the underlying physical processes at the interface as the relevant electronic states and electrostatic interactions are highly dependent on the molecular packing confi gurations between the donor and acceptor molecules or chain segments. [ 3 , 13-16 , 17 ] Hence, to achieve optimal OPV performance, one must be able to understand and ultimately control the morphology of these heterojunctions. [ 12 ] OPVs based solely on small molecule donors and acceptors have recently shown considerable improvement, [ 4 , 18 ] with power conversion effi ciencies for (solution-processed) singlejunction devices reaching 6.7% [ 19 ] and (vacuum-deposited) tandem devices surpassing 10.7%. [ 20 ] Small-molecule active layers employing pentacene as the electron donor and C 60 as the electron acceptor have served as prototype systems to detail a number of key features of OPVs. [ 21 , 22 ] Due to the relatively small size and rigid structural characteristics of these molecules, the pentacene-C 60 interface has also undergone a number of theoretical investigations, ranging from electronic-structure calculations on molecular complexes to atomistic molecular dynamics (MD) simulations. [ 13-15...

The equatorial deep jets (EDJ) are a striking feature of the equatorial ocean circulation. In

The Atlantic Meridional Overturning Circulation (AMOC) is crucially important to global climate. Model simulations suggest that the AMOC may have been weakening over decades. However, existing array-based AMOC observations are not long enough to capture multidecadal changes. Here, we use repeated hydrographic sections in the subtropical and subpolar North Atlantic, combined with an inverse model constrained using satellite altimetry, to jointly analyze AMOC and hydrographic changes over the past three decades. We show that the AMOC state in the past decade is not distinctly different from that in the 1990s in the North Atlantic, with a remarkably stable partition of the subpolar overturning occurring prominently in the eastern basins rather than in the Labrador Sea. In contrast, profound hydrographic and oxygen changes, particularly in the subpolar North Atlantic, are observed over the same period, suggesting a much higher decoupling between the AMOC and ocean interior property fields than previously thought.