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1. The composition of Mars

   https://doi.org/doi:10.1016/j.gca.2020.01.011  

   Yoshizaki, Takashi; McDonough, William F. (March 2020, Geochimica et cosmochimica acta)

   Comparing compositional models of the terrestrial planets provides insights into physicochemical processes that produced planet-scale similarities and differences. The widely accepted compositional model for Mars assumes Mn and more refractory elements are in CI chondrite proportions in the planet, including Fe, Mg, and Si, which along with O make up >90% of the mass of Mars. However, recent improvements in our understandings on the composition of the solar photosphere and meteorites challenge the use of CI chondrite as an analog of Mars. Here we present an alternative model composition for Mars that avoids such an assumption and is based on data from Martian meteorites and spacecraft observations. Our modeling method was previously applied to predict the Earth’s composition. The model establishes the absolute abundances of refractory lithophile elements in the bulk silicate Mars (BSM) at 2.26 times higher than that in CI carbonaceous chondrites. Relative to this chondritic composition, Mars has a systematic depletion in moderately volatile lithophile elements as a function of their condensation temperatures. Given this finding, we constrain the abundances of siderophile and chalcophile elements in the bulkMars and its core. The Martian volatility trend is consistent with <7 wt% S in its core, which is significantly lower than that assumed in most core models (i.e., >10 wt% S). Furthermore, the occurrence of ringwoodite at the Martian core-mantle boundary might have contributed to the partitioning of O and H into the Martian core. 

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2. The Chemical Composition of the Sun

   https://doi.org/10.5281/zenodo.14988840  

   Bergemann, Maria; Lodders, Katharina; Palme, Herbert (January 2025, Elsevier and Zenodo)

   {"Abstract":["Machine-readable tables accompany the book chapter "Chemical Composition of the Sun", authors Maria Bergemann, Katharina Lodders, Herbert Palme,  Encyclopedia of Astrophysics 1st Edition (edited by I. Mandel, section editor F.R.N. Schneider) to be published by Elsevier as a Reference Module, 2025"]} 

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3. The composition complexity of majority

   Lecomte; Victor; Ramakrishnan, Prasanna; Tan; Li-Yang (January 2022, Leibniz international proceedings in informatics)
4. The Molecular Composition of Soot

   https://doi.org/10.1002/anie.201914115  

   Jacobson, Rachelle S.; Korte, Andrew R.; Vertes, Akos; Miller, J. Houston (January 2020, Angewandte Chemie International Edition)

   Abstract Soot (sometimes referred to as black carbon) is produced when hydrocarbon fuels are burned. Our hypothesis is that polynuclear aromatic hydrocarbon (PAH) molecules are the dominant component of soot, with individual PAH molecules forming ordered stacks that agglomerate into primary particles (PP). Here we show that the PAH composition of soot can be exactly determined and spatially resolved by low‐fluence laser desorption ionization, coupled with high‐resolution mass spectrometry imaging. This analysis revealed that PAHs of 239–838 Da, containing few oxygenated species, comprise the soot observed in an ethylene diffusion flame. As informed by chemical graph theory (CGT), the vast majority of species observed in the sampled particulate matter may be described as benzenoids, consisting of only fused 6‐membered rings. Within that limit, there is clear evidence for the presence of radical PAH in the particulate samples. Further, for benzenoid structures the observed empirical formulae limit the observed isomers to those which are nearly circular with high aromatic conjugation lengths for a given aromatic ring count. These results stand in contrast to recent reports that suggest higher aliphatic composition of primary particles. 

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5. Composition, structure, and origin of the Moon

   Sossi, Paolo A; Nakajima, M; Khan, A (September 2024, Treatise on Geochemistry (Third Edition))