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We present a suite of ALMA interferometric molecular line and continuumimages that elucidate, on linear size scales of $\sim$30--40 AU, the chemicalstructure of the nearby, evolved, protoplanetary disk orbiting the close binarysystem V4046 Sgr. The observations were undertaken in the 1.1--1.4 mmwavelength range (ALMA Bands 6 and 7) with antenna configurations involvingmaximum baselines of several hundred meters, yielding subarcsecond-resolutionimages in more than a dozen molecular species and isotopologues. Isotopologuesof CO and HCN display centrally peaked morphologies of integrated emission lineintensity, whereas the line emission from complex nitrile group molecules(HC$_3$N, CH$_3$CN), deuterated molecules (DCN, DCO$^+$), hydrocarbons (astraced by C$_2$H), and potential CO ice line tracers (N$_2$H$^+$, and H$_2$CO)appears as a sequence of sharp and diffuse rings. The dimensions andmorphologies of HC$_3$N and CH$_3$CN emission are suggestive of photodesorptionof organic ices from the surfaces of dust grains, while the sequence ofincreasing radius of peak intensity represented by DCN (smallest), DCO$^+$,N$_2$H$^+$, and H$_2$CO (largest) is qualitatively consistent with the expecteddecline of midplane gas temperature with increasing disk radius. Empiricalmodeling indicates that the sharp-edged C$_2$H emission ring lies at relativelydeep disk layers, leaving open the question of the origin of C$_2$H abundanceenhancements in evolved disks. This study of the "molecular anatomy" of V4046Sgr should serve as motivation for additional subarcsecond ALMA molecular lineimaging surveys of nearby, evolved protoplanetary disks aimed at addressingmajor uncertainties in protoplanetary disk physical and chemical structure andmolecular production pathways.

A Subarcsecond ALMA Molecular Line Imaging Survey of the Circumbinary, Protoplanetary Disk Orbiting V4046 Sgr