Introduction to high-pressure science

1. Introduction to high-pressure science Przemyslaw Dera Center for Advanced Radiation Sources The University of Chicago Argonne National Laboratory Advanced Photon Source NATO Science for Peace and Security Program Advanced Study Institute International School on High Pressure Crystallography Erice, Italy, June 4-14, 2009

2. Why High Pressure? • Pressure spans in the visible universe over 60 orders of magnitude, from the non-equilibrium pressure of hydrogen in intergalactic space, to the kinds of pressure encountered within neutron stars. • It provides unique possibility to control structure and properties of materials, dramatically alter electronic properties, break existing, or form new chemical bonds, by reaching compressions in excess of an order of magnitude for molecular materials. • The free energy change associated with this degree of compression can be in the order of 10 eV, exceeding the strength of the strongest molecular bonds. • The pressure induced changes in chemical affinities can significantly alter reactivity of elements and compounds, opening door to synthesis of new classes of materials. “Scientists around the world are now racing to harness the power of yet another of nature’s forces - the force of high pressure. (…) They have subjected ordinary sand to tons of pressure to shed light on the extinction of the dinosaurs. (…) They have used high pressure to transform any carbon-rich material, from road tar to peanut butter, into the most prized of gems - diamonds.” Robert Hazen, 1993 “The New Alchemists. Breaking through the barriers of high pressure.”

3. What is pressure? • Pressure (scalar) • P=F/A • F - normal force • A – area on which the force acts • Stress (tensor) •  - stress tensor components •  - strain tensor components • C – elastic compliances

4. 1969 1979 1989 364 329 136 24 0 When is pressure high? Pressure scale: 1GPa Sample size <0.3mm Sample thickness<0.1mm Most proteins denaturate 10 GPa Sample size <0.05mm Sample thickness<0.05mm All subtances solidify 100 GPa Sample size <0.01mm Sample thickness<0.005mm All “organics” amorphize

5. Multidisciplinary science of high pressure • Physics • Chemistry • Geophysics • Materials science and engineering • Biology • Energy science • (energy storage, fuels, high energy density materials, explosives, shock physics) Common ground • Physics • Interatomic interaction potentials • Thermodynamic driving forces of transformations • Chemistry • Hydrostatic vs. osmotic • Chemical potentials • Reactions

6. High-pressure phenomena • Structural phase transitions • Reconstructive • Displacive • Order-disorder • Electronic transitions • Metal-insulator • High-spin low-spin • Superconductivity • Magnetic transitions • Melting • Amorphisation • Chemical transformations • Osmotic • Chemical reactions • Continuous changes in the physical properties

7. Touch of history

8. He found it necessary to design his own experimental equipment, including static and dynamic seals for fluids in excess of 3 GPa utilizing his original recognition of the principle of "unsupported area" The mushroom shaped piece (a) is free to move in the socket piece (e) with variations of pressure. The area of its stem is the unsupported area. The soft packing (c) is squeezed in the annulus between the socket piece (e) and the mushroom head (a) to pressure slightly in excess of the system pressure (P). The triangular shaped cross sectional pieces of bronze (b) move to prevent extrusion of the soft packing. The packing is self-sealing to approximately 3 GPa. Percy W. Bridgman (1882-1961) Harvard University He has carried out extensive investigations on the properties of matter at pressures up to 10 GPa including a study of the volume compressibility, electric and thermal conductivity, tensile strength and viscosity of more than 100 different compounds. 1946 Nobel Prize in Physics for his work on the physics of high pressure Bridgman, P. W. 1911. Water, in the liquid and five solid forms, under pressure. Proc. Am. Acad. Arts Sci. 47:441-558. McMillan (2005) Nature Materials, 4, 715

9. Charles Weir, Alvin van Valkenburg, Gasper J. Piermarini • National Bureau of Standards (now NIST) 1959 Opposed anvil geometry DAC 1964 metal foil gasketing technique Pioneered single-crystal XRD Pioneered high pressure studies of molecular materials Piermarini (2001) J. Res. NIST, 106, 889 Crystal of benzene grown from liquid

10. John D. Bernal (1901-1971), Cambridge University In 1928 Bernal predicted that all matter should ultimately become metallic at sufficient pressure, as the forced overlap of electron orbitals induces electron delocalization. High-pressure transformations from insulator to metal were first observed in iodine, silicon, germanium, and other elements by Drickamer et al. In 1936 came up with hypothesis that a phase transition in olivine might be the cause of discontinuities in the observed in the earthquake travel times. Worked on the description of the structure of liquid water.

11. A. Francis Birch (1903-1992) Harvard University In 1952 he published a well-known paper where he demonstrated that the Earth mantle is mainly composed of silicate minerals, the upper and lower mantle are separated by a thin transition zone associated with silicate phase transitions, and the inner and outer core are alloys of crystalline and molten iron. In 1947, he adapted the isothermal Murnaghan equation of state, which had been developed for infinitesimal strain, for Eulerian finite strain, developing what is now known as the Birch-Murnaghan equation of state. In 1961, Birch published two papers on compressional wave velocities establishing a linear relation (now called Birch's law) of the compressional wave velocity Vp of rocks and minerals of a constant average atomic weight with density ρ. "Unwary readers should take warning that ordinary language undergoes modification to a high-pressure form when applied to the interior of the Earth. A few examples of equivalents follow:" High Pressure Form Ordinary Meaning Certain Dubious Undoubtedly Perhaps Positive proof Vague suggestion Unanswerable argument Trivial objection Pure iron Uncertain mixture of all the elements

12. William A. Bassett Cornel University First deterimination of high-pressure phase of iron First observation of phase transition from spinel to lower mantle phases Co-inventor of the laser-heating method and spectroscopic temperature measurement Design of the Merrill-Bassett DAC

13. Automated and optimized single-crystal XRD experiments in DAC • Determined compression mechanisms of ~100 minerals up to pressure reachable in Merrill-Bassett DAC. • Formulated foundations of the comparative crystal chemistry in p-T-X space. Larry W. Finger and Robert M. Hazen, Carnegie Institution

14. Strategies for success in high-pressure science • High pressure research is to a large extent an exploratory experimental discipline, in which many extraordinary discoveries come by surprise. A wise strategy for the explorationis usually the key to success. • Mastering a single technique and improvement/optimization of it to the “state of the art” level provides a high-pressure researcher with a unique vehicle for this exploration. • Seek additional information from complementary methods once an interesting phenomenon has been identified.

15. Major experimental and theoretical methods X-ray and neutron diffraction Raman and IR spectroscopy Optical absorption spectroscopy X-ray absorption spectroscopy X-ray emission spectroscopy X-ray Raman spectroscopy Conventional and synchrotron Mossbauer spectroscopy Inelastic scattering Brillouin spectroscopy and ultrasonic measurements Magnetic susceptibility measurements Electrical conductivity measurements

16. Mineral Physics Properties of earth-forming minerals at geo-relevant conditions Phase transitions in earth forming minerals Melting relations Element partitioning Shock metamorphism Rheology

17. Post-perovskite story • MgSiO3 perovskite is thought to be one of the principal mineral phases present in the upper part of Earth lower mantle. • For many ears it was assumed that pv either remains stable in its original structure or decomposes into oxides as p and T progress along the geotherm. • Resent studies demonstrate that most of perovskite structures transform into ppv at high pT conditions. • ppv exhibits physical properties markedly different from pv. Murakami et al. (2004) Science, 304, 855 Oganov and Ono (2004) Nature 430, 445 Wentzcovitch et al. (2006) PNAS, 103, 543

18. Extraterrestrial minerals and shock metamorphism Post-stishovite polymorph of silica Sharp et al. (1999) Sciecne, 284, 1511 Dubrovinskaya et al. (2001) Eur. J. Mineral. 13, 479 Dera et al (2003) Am. Mineral., 87, 1018 El Gorezy (2008) Eur. J. Mineral. 20, 523 Meteorite name Shergotty Location Found Shergotty, India Date Found August 25, 1865 Mass (g) ~5,000 Type Shergottite (SNC) Radiometric age (x109 years) 0.16±0.01 Barringer crater, AZ

19. Materials science and engineering New technological materials synthesis Tuning materials properties Stress/strain relations Materials stability limits

20. Tuning materials properties: Ferroelectric PbTiO3 and pressure-induced morphotropic transition • Piezoelectric materials exhibit a morphotropic phase boundary associated with symmetry lowering and maximization of electromechanical properties. • Morphotropic transitions are usually triggered by change in composition. • In PbTiO3 morthotropic transition was demonstrated to occur as a function of pressure at low temperature. Ahart (2008) Nature, 451, 545

21. Synthesis of noble metal nitrides from elements High p-T synthesis of platinum nitride Gregoryanz et al. (2004) Nature Matrials, 3, 294 High p-T synthesis of indium nitride Crowhurst et al. (2006) Science, 311, 1275

22. Chemistry Solid-state reactions Changes of chemical potentials Osmotic reactions High-pressure polymerization

23. Bonding changes in high-pressure phase of oxygen • Oxygen is the only diatomic molecule that has a magnetic moment. • Solid oxygen becomes metallic at pressure close to 100 GPa. • Epsilon or “red” oxygen was discovered by Nicol et al. (1979), Chem. Phys. Lett. 68, 49 • Space group and tentative model were proposed by Johnson et al. 1993, J. Appl. Cryst. 26, 320 • Correct model of the crystal structure of epsilon oxygen exhibiting occurrence of (O2)4 molecular units was determined by Lundegaard et al. (2006) Nature, 443, 201

24. Bonding changes in CO2 Infrared spectra show formation of single bonds Amorphous phase of CO2 (carbonia) Santoro et al. (2006) Nature, 441, 857 Co2

25. Physics Structural phase transitions Electronic and magnetic transitions Response to pressure in continuous compression regime

26. Mott-Hubbard transition in Fe2O3 Pasternak et al. (1999) PRL 82, 4663 Badro et al. (2002) PRL 89, 205504

27. Corundum structure Rh2O3-II structure

28. H-bond symmetrization in ice Hydrogen bond symmetrization in phase D Tsuchiya et al. (2005) Am. Mineral. 90, 44-49 Hydrogen bond symmetrization in H2O ice Goncharov et al. (1996) Science, 273, 218-220

29. Biology Thermodynamic limits of life and habitability Possible role of high pressure environments in the origins of life on Earth Response (stress and adaptation) of organisms and biomolecules to high pressure Understanding extremophiles The “mechanics” of enzyme molecules

30. High pressure crystallography and biology Daniel et al. (2006) Chem. Soc. Rev., 35, 858 Extremely barophilic bacteria isolated from the Mariana Trench, Chal lenger Deep, at a Depth of 11,000 Meters Kato et al. (1998) Appl. Envir. Microbiol., 64, 1510

31. Food preparation technology • High pressure (HP) treatment causes unique effects on proteins and other food components that could be advantageously used in the dairy industry. Although commercial application of HP technology is currently limited to the processing of guacamole, oysters, juices and fruit jams and jellies, this technology offers potential to be applied in cheese manufacture. • Pressurization of milk causes conformational changes of milk proteins. On the one hand, HP treatment decreases the size and increases the number of naturally occurring casein micelles, thus, depending on treatment temperature. Denaturation occurs reversibly at pressure treatments below 200MPa, however, at higher pressures irreversible denaturation increases with increasing pressure. • HP treatment technology offers the advantage of shortening ripening times in cheese making [San Martin-Gonzalez et al., 2004, IFT Annual Meeting, Las Vegas ]. Wort, as well as end-processing beer from barley can be pressurized and different parameters related to the beer quality were measured to assess the influence of High Pressure Treatment (HPT). Bitterness, iso-a-acids, and total a-acids were reduced in wort after applying high pressures. Foam, haze and chill haze, and saturated ammonium sulphate precipitation limit were increased in beer with high pressures. There is a chance for the industrial application of HPT to reduce wort bitterness. The foaming characteristics and the colloidal stability of beer can also be enhanced with this treatment [Perez-Lamela et al. (2004) Deutsche Lebensmittel-Rundschau, 100, 53 ]. Hendrick and Knorr Eds. (2002) “Ultra High Pressure Treatment of Food Engineering” Kluwer Academic/Plenum Publishers

32. Medical applications Hyperbaric oxygen therapy Typical pressure used is 1.5 bar Several therapeutic principles are uses in HBOT: • The increased overall pressure is of therapeutic value when HBOT is used in the treatment of decompression sickness and air embolism. • For many other conditions HBOT drastically increases partial pressure of oxygen in the tissues of the body. A related effect is the increased oxygen transport capacity of the blood plasma. Gill and Bell “Hyperbaric oxygen: its uses, mechanisms of action and outcomes” (2004) QJM. 97, 385 High-pressure Neurological Syndrome High-pressure neurological syndrome (HPNS) is a condition encountered in diving beyond a depth of 100 m. Manifestations include headache, tremor, myoclonus, neuropsychiatric disturbances and EEG changes. Convulsions are seen only in experimental animals. Most of the changes are reversible on surfacing but some such as memory disturbances may linger on for long periods Talpalar “High pressure neurological syndrome” (2007) Rev. Neurol. 45, 631

33. Role of crystallography in high pressure science • Modern crystallography is defined much broader than just diffraction experiments, it includes many scattering and spectroscopy techniques, as well as theoretical modeling approaches. • Crystallographic techniques are used not only to study the structure of crystalline solids, but apply also to amorphous substances, liquids, thin films, etc. • Crystallographic experiments and simulations provide the link between the micro-world of atoms and interatomic interaction and macro-world of physical properties and chemical transformations. • W/o crystallographic characterization (atomistic model) most high-pressure phenomena can only be understood at a descriptive level.

34. Central facilities for high-pressure research • USA • Argonne National Laboratory, APS (Chicago, IL) • Brookhaven National Laboratory, NSLS (Brookhaven, NY) • Lawrence Berkley National Laboratory, ALS (Berkley, CA) • CHESS (Ithaca, NY) • Oak Ridge National Laboratory, SNS (Oak Ridge, TN) • UK • Diamond • Daresbury • ISIS • Japan • SPRING-8 • Photon Factory • Germany • DESY/HASYLAB (Hamburg) • France • ESRF (Grenoble) • ILL (Grenoble) • Soleil (Paris) • Russia • Dubna

35. High-pressure community organizations European High Pressure Research Group (EHPRG) www.ehprg.org • Established in 1963 • EHPRG award • Organizes annual meeting, often combined with AIRAPT International Association for the Advancement of High Pressure Science and Technology (AIRAPT) www.ct.infn.it/airapt/ • Established in 1965, grew out of the Community of Gordon Research Conferences on Research at High pressure • organizes biennal conferences often combined with EHPRG • Awards Bridgman Award International Union of Crystallography Commission on High-Pressurewww.iucr.org/iucr/commissions/chp.html • Established in 1987 • Organizes annual workshops and high-pressure focus sessions at International Crystallographic Congress Consortium for Materials Research in Earth Sciences (COMPRES) www.compres.us • Established in 2001 by a grant from National Science Foundation • Coordinates and maintains high-pressure synchrotron beamlines in USA • Organizes annual meeting

36. Future from first explorers to colonization • High pressure science receives increasing recognition and interest from funding agencies and management of central facilities. • Excellent advanced experimental tools and methods are now available for the general community at central facilities. • Extending the limits of experimental techniques (pressure, temperature, magnetic field). • Extending high-pressure crystallographic techniques to time-resolved domain. • Extending the subjects of investigation to more complex materials. • Increasing real technological applications of high-pressure discoveries.

37. Acknowledgements Very special thanks to Lodovico Riva Di San Severino, Paola Spadon, John Irvin and Elena Pappinutto and all the lecturers They made this school possible!!!