june 4no 11-annual report 2015 ying mi

1、On the compression to NaClHPSTAR Annual Report Zhongying MIJune 3nd, 2015Outline1. On the compression to NaCl Extension of Phase transition Non-hydrostaticityNano-sized Effects2. Water Effect on Olivine StrengthTextureNaCl25x1027 nm3323 nm39.1 GPaB 2 phase31.4 GPaB 1+B 2 phaseB 1 phase29.5 GPa250x10

2、B 2_ 100B 2 phase20Intensity15A u111B 1+B 2 phase43.1 GPaB 1_ 111B 1_ 200A u_ 111B 1_ 331A u_ 22032.4 GPa200IntensityB 2_ 100B 2_ 110B 2_ 200150B 1_ 111B 1_ 200B 2 110M gO 200B 1_ 22010B 1 phase529.2 GPa100509B 2 20010111213A u_ 200B 1_ 220141516171819202122910111213141516171819202122P ressure ( G P

3、 a)B2B1+B2B150P ressure ( G P a)4540Pressure (GPa)353025200.00.20.40.60.81.0NaCl 100%MgO 100%Two Potential Explanations1. Hydrostaticity2. Nano-effectNaCl _r-EDXDNaClr-XRDNaCl (run 1)ADXDNaCl (run 2)ADXD axialno pressure medium25% MgO25% MgOrun 1run 2stresstextureNaCl-MgOr-XRD33% MgO50% MgOrun 1stre

4、ss50% MgO75% MgOrun 2textureaxial20% MgO80% MgOmethenol-ethonal PM methanol-ethanol PM Durandurdu M. The structural phase transition of ZnSe under hydrostatic and nonhydrostatic compressions: an ab initio molecular dynamics study. J Phys Condens Matter. 2009 Mar 25;21(12):125403. doi:10.1088/0953-89

5、84/21/12/125403. Epub 2009 Feb 26. Murat Durandurdu Diamond to -Sn phase transition of silicon under hydrostatic and nonhydrostatic compressions 2008 J. Phys.: Condens. Matter 20 325232 doi:10.1088/0953-8984/20/32/325232 Noorussaba, Afaq Ahmad. Phase transition study in a Cu2HgI4:0.2AgI mixedcomposi

6、te system doped with K2SO4, November 2011, Volume 17, Issue 8, pp 759-766 Lkhamsuren Bayarjargal. Influence of grain size, surface energy, and deviatoric stress on the pressure-induced phase transition of ZnO and AlN, High Pressure Research: An International Journal, pages 642-651OI:10.1080/08957959

7、.2013.800514 Liu Shao-Jun, Structure phase transition from to in Fe under non-hydrostatic pressure: an ab initio study Acta Phys. Sin.2009, Vol. 58 Issue (3): 2083-2089 Yuki Asahara, Acoustic velocity measurements for stishovite across the post-stishovite phase transition under deviatoric stress: Im

8、plications for the seismic features of subducting slabs in the mid-mantle, American Mineralogist. Volume 98, Issue 11-12, Pages 20532062, ISSN,1945-3027, ISSN (Print) 0003-004X, DOI: 10.2138/am.2013.4145, March 2015 Hydrostaticity-bring phase transition earlier!Create more defect, atoms move faster,

9、phase transition earlierBoehler, 1990, JGRNano-effect300shapeSurface energy increased as size reduce, elevate the transition pressure200B127 nm1to1_new(200)(222)(220)B2(110)(200)(211)Size (Angstrom)1000B2B1+B2B1555045Size-dependent bulk modulus of B1 NaCl40Ko(GPa)45Transition Pressure (GPa)354030352

10、5203015010203040506025D(nm)2020304050Size (nm)800010000NaClAu pressure standard400600020 nmB1_111Size (angstrom)300B1_200Au_111Au_200B1_220B1_3314000B1_222200020008.59.09.510.010.511.011.512.012.513.013.514.014.515.015.516.016.517.017.518.0100Gold peak quite weak compare to NaCl, the sizeof Au is 20

11、 nm, and NaCl is with the sameparticle size Au_size_13n B1_size_13n B1_size_11n Au_size_11n01020304050Pressure (GPa)Green symbol=NaCl B1 phase=sizedecrease continuouslyGolden color=Au=size decrease at beginning, keep stable after 10 GPa.SEM of Au at 1 BarSherre equationGerward, 1976Singh, 2004He, 20

12、04100 nm40-80 nmSize calculated by Jade software MgO act as energy barrier So the lattice preferred orientation Hinder the phase transition of B1 to B2Single phasemulti phase10.8 GPa14.0 GPa30.3 GPa31.5 GPa1 Bar4.8 GPa13.3 GPa24.9 GPa30.0 GPa32.1 GPa37.1 GPaSingle NaCl phase vs NaCl in NaCl-MgO (1:1

13、)Single phasemulti phase30.3 GPa32.8 GPa34.4 GPa37.9 GPa45.9 GPa56.4 GPa32.1 GPa35.0 GPa37.1 GPa40.6 GPaSingle NaCl phase vs NaCl in NaCl-MgO (1:1)?Late ExtendFinish it!Water Effect on Olivine Nestola11_Fo60Fa40 Nestola11_Fo70Fa30 Nestola11_Fo80Fa20 Liu06 Downs96 Brodholt96 Hy_this studyOlFodry oliv

14、inewet olivine hy_our hy_Fo_Jacobsen08 hy_Mao12 dry_our dry_Fo_Jacobsen08 dry_Jochym04240290Cell Volume (cubic angstrom)220Bulk Modulus (GPa)280200270180260160250140240051015202530051015202530Pressure (GPa)Pressure (GPa)生石凌了句120.0100.080.08。01至lePP)fE2PeoooII I I10.012.014.016.0P1021.2 GPaP111 BarP11 Bar P711.4 GPaP20.4 GPaP813.7 GPaP69.3 GPaP917.1 GPa P121 BarHydrous olivineNonhydrous olivine5.2 GPa6.3 GPa7.9 GPa21.89.0 GPa12.9 GPaGPaAcknowledgment Bin Chen, Ho-Kwang Mao, Qiaoshi Zeng, Zid