Structure, thermodynamics, and diffusion in CaAl2Si2O8 liquid from first-principles molecular dynamics

First principles molecular dynamics simulations of diopside (CaMgSi2O6) liquid to high pressure

“…The change is substantial: nearly a factor of 3 on twofold compression. Similar behavior is seen in all the liquids that we have studied to date, including MgSiO 3 , Mg 2 SiO 4 , MgO, SiO 2 , and CaAl 2 Si 2 O 8 (Stixrude and Karki, 2005;Karki et al, 2006Karki et al, , 2007de Koker et al, 2008;de Koker, 2010). We have argued that the increase in the Grü neisen parameter on compression is related to the increase in coordination number: the liquid appears to track the increase in c on going from low-pressure to high-pressure crystalline polymorphs (Stixrude and Karki, 2005).…”

“…Previous molecular dynamics simulations of CaO-MgO-SiO 2 liquids have been based on semi-empirical interionic potentials (Angell et al, 1987;Matsui, 1996;Zhang et al, 2010). The advantage of FPMD is that it is non-empirical, thereby allowing predictions that are independent of experiment and which, as shown in previous FPMD studies on silicate liquids, agree very well with experimental measurements (Stixrude and Karki, 2005;de Koker et al, 2008;Mookherjee et al, 2008;de Koker, 2010). We investigate the thermodynamic properties and structure of the liquid.…”

“…The thermodynamic properties of the melt are analyzed according to the fundamental relation recently proposed (de Koker andStixrude, 2009, 2010). Briefly, the functional form is specified by the Helmholtz free energy…”

Neutron diffraction of calcium aluminosilicate glasses and melts

“…CAS melts are also the main components of slags produced in furnaces in coal and steel industries. In geosciences, they are of fundamental importance as they form a significant fraction of the composition of geological magmas [5,6,7].…”

Structure, thermodynamic and transport properties of liquid MgSiO3: Comparison of molecular models and laboratory results

“…The ultimate goal is to develop quantitative models for the properties of multicomponent silicate liquids spanning the P-T range relevant to terrestrial planet evolution consistent with experimental and theoretical constraints. There has already been success in the study of silicate liquids using this approach and even a cursory review of the computational literature applicable to high temperature liquids relevant to geochemical problems (magma end member compositions and molten iron) over the past thirty years reveals a rapid expansion in knowledge with accuracies comparable to experimental studies (e.g., Angell et al, 1982;Dempsey and Kawamura, 1984;Angell et al, 1987;Kubicki and Lasaga, 1990;Rustad et al, 1990;Della Valle and Andersen, 1992;Rustad et al, 1992;Poole et al, 1995;Stein and Spera, 1995;Bryce et al, 1998;Nevins and Spera, 1998;Morgan and Spera, 2001;Alfe et al, 2002;Stixrude and Karki, 2005;Guillot and Sator, 2007a,b;Lacks et al, 2007;Wan et al, 2007;de Koker et al, 2008;Martin et al, 2009;Nevins et al, 2009;Spera et al, 2009;Vuilleumier et al, 2009;de Koker, 2010). Research is accelerating due to the development of increasingly robust algorithms and the wide availability of computational engines.…”