<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">D. Huang</style></author><author><style face="normal" font="default" size="100%">Brodholt, J.</style></author><author><style face="normal" font="default" size="100%">Sossi, P.</style></author><author><style face="normal" font="default" size="100%">Y. Li</style></author><author><style face="normal" font="default" size="100%">Murakami, M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nitrogen Speciation in Silicate Melts at Mantle Conditions From Ab Initio Simulations</style></title><secondary-title><style face="normal" font="default" size="100%">Geophysical Research Letters</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">ab initio</style></keyword><keyword><style  face="normal" font="default" size="100%">atmosphere</style></keyword><keyword><style  face="normal" font="default" size="100%">fugacity</style></keyword><keyword><style  face="normal" font="default" size="100%">high pressure</style></keyword><keyword><style  face="normal" font="default" size="100%">magma ocean</style></keyword><keyword><style  face="normal" font="default" size="100%">nitrogen speciation</style></keyword><keyword><style  face="normal" font="default" size="100%">oxygen</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2022</style></year><pub-dates><date><style  face="normal" font="default" size="100%">apr</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL095546</style></url></web-urls></urls><number><style face="normal" font="default" size="100%">7</style></number><volume><style face="normal" font="default" size="100%">49</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Nitrogen (N) is a major ingredient of the atmosphere, but a trace component in the silicate Earth. Its initial inventory in these reservoirs during Earth&amp;#039;s early differentiation requires knowledge of N speciation in magmas, for example, whether it outgasses as N 2 or is sequestered in silicate melts as N 3− , which remains largely unconstrained over the entire mantle regime. Here we examine N species in anhydrous and hydrous pyrolitic melts at varying P‐T‐redox conditions by ab‐initio calculations, and find N‐N bonding under oxidizing conditions from ambient to lower mantle pressures. Under reducing conditions, N interacts with the silicate network or forms N‐H bonds, depending on the availability of hydrogen. Redox control of N speciation is demonstrated valid over a P‐T space encompassing probable magma ocean depths. Finally, if the Earth accreted from increasingly oxidized materials toward the end of its accretion, an N‐enriched secondary atmosphere might be produced and persist until later impacts.</style></abstract></record></records></xml>