Contribución al estudio de los hongos que fructifican sobre la familia Pinaceae (Gen. Pinus L.) en Espana (1ª aportación)

In order to determine wether there is any specific group of fungi able to fructify on plant debris from the genus Pinas L., a Sheme of work was made, introducing new signs for it. 8 new taxons are described, being a contribution to the spanish mycological catalogue. The presence in Spain of Ascobolus archeri formely known only in Tasmania (Australia) should be pointed out.Se realiza un ensayo de trabajo para determinar ciertos grupos de hongos específicos o que muestren apetencia a fructificar sobre restos vegetales del género Pinus, introduciendo signos determinados para estos estudios. Resultan nuevas aportaciones al catálogo micológico español los ocho siguientes tazones: Ascobolus arcberi, Coniophorella olivacea, Oidium candicans, Hypboderma argillaceum, Hypboderma pallidum, Hipochnicium eichleri, Galerina autumnalis y Galerina stylifera. De las cuales Ascobolus archeries nueva cita para Europa

Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, un discomicete con incidencia en la truficultura e interés forestal

Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, a cup-shaped ascomycete related with truffle cultures and afforestation. A casual finding of Sphaerosporella brunnea in some greenhouses from Spain, growing in connection with several ectomycorrhizal plants, is reported. These plants were experimentally inoculated with low level inoculum of Tuber melanosporum. Sphaerosporella brunnea is described and illustrated, and its negative role in truffle cultures and its possible utilization in burned are as recovery is emphasized.Se da cuenta del hallazgo casual, en unos viveros españoles de Sphaerosporella brunnea, formando micorrizas con plantas diversas, las cuales habían sido inoculadas experimentalmente con niveles bajos de Tuber melanosporum. Se describe e ilustra esta especie, al tiempo que se destaca su papel negativo en la truficultura y su posible utilización en la recuperación de áreas incendiadas

Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, un discomicete con incidencia en la truficultura e interés forestal

Se da cuenta del hallazgo casual, en unos viveros españoles de Sphaerosporella brunnea, formando micorrizas con plantas diversas, las cuales habían sido inoculadas experimentalmente con niveles bajos de Tuber melanosporum. Se describe e ilustra esta especie, al tiempo que se destaca su papel negativo en la truficultura y su posible utilización en la recuperación de áreas incendiadas.Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, a cup-shaped ascomycete related with truffle cultures and afforestation. A casual finding of Sphaerosporella brunnea in some greenhouses from Spain, growing in connection with several ectomycorrhizal plants, is reported. These plants were experimentally inoculated with low level inoculum of Tuber melanosporum. Sphaerosporella brunnea is described and illustrated, and its negative role in truffle cultures and its possible utilization in burned are as recovery is emphasized

The evolution of H{\sc ii} galaxies: Testing the bursting scenario through the use of self-consistent models

We have computed a series of realistic and self-consistent models of the emitted spectra of H{\sc ii} galaxies. Our models combine different codes of chemical evolution, evolutionary population synthesis and photoionization. The emitted spectrum of H{\sc ii} galaxies is reproduced by means of the photoionization code CLOUDY, using as ionizing spectrum the spectral energy distribution of the modelled H{\sc ii} galaxy, which in turn is calculated according to a Star Formation History (SFH) and a metallicity evolution given by a chemical evolution model that follows the abundances of 15 different elements. The contribution of emission lines to the broad-band colours is explicitly taken into account. The results of our code are compared with photometric and spectroscopic data of H{\sc ii} galaxies. Our technique reproduces observed diagnostic diagrams, abundances, equivalent width-colour and equivalent width-metallicity relations for local H{\sc ii} galaxies.Comment: 13 figures and 2 tables, accepted for publication in MNRAS Main Journa

High-pressure optical absorption in InN: Electron density dependence in the wurtzite phase and reevaluation of the indirect band gap of rocksalt InN

We report on high-pressure optical absorption measurements on InN epilayers with a range of free-electron concentrations (5×1017–1.6×1019 cm−3) to investigate the effect of free carriers on the pressure coefficient of the optical band gap of wurtzite InN. With increasing carrier concentration, we observe a decrease of the absolute value of the optical band gap pressure coefficient of wurtzite InN. An analysis of our data based on the k·p model allows us to obtain a pressure coefficient of 32 meV/GPa for the fundamental band gap of intrinsic wurtzite InN. Optical absorption measurements on a 5.7-μm-thick InN epilayer at pressures above the wurtzite-to-rocksalt transition have allowed us to obtain an accurate determination of the indirect band gap energy of rocksalt InN as a function of pressure. Around the phase transition (∼15 GPa), a band gap value of 0.7 eV and a pressure coefficient of ∼23 meV/GPa are obtained. ©2012 American Physical SocietyThis work was supported by the Spanish Ministry of Science and Innovation through Project No. MAT2010-16116.Ibáñez, J.; Segura, A.; García-Domene, B.; Oliva, R.; Manjón Herrera, FJ.; Yamaguchi, T.; Nanishi, Y.... (2012). High-pressure optical absorption in InN: Electron density dependence in the wurtzite phase and reevaluation of the indirect band gap of rocksalt InN. Physical Review B. 86:35210-1-35210-5. https://doi.org/10.1103/PhysRevB.86.035210S35210-135210-586Wu, J. (2009). When group-III nitrides go infrared: New properties and perspectives. Journal of Applied Physics, 106(1), 011101. doi:10.1063/1.3155798Ueno, M., Yoshida, M., Onodera, A., Shimomura, O., & Takemura, K. (1994). Stability of the wurtzite-type structure under high pressure: GaN and InN. Physical Review B, 49(1), 14-21. doi:10.1103/physrevb.49.14Uehara, S., Masamoto, T., Onodera, A., Ueno, M., Shimomura, O., & Takemura, K. (1997). Equation of state of the rocksalt phase of III–V nitrides to 72 GPa or higher. Journal of Physics and Chemistry of Solids, 58(12), 2093-2099. doi:10.1016/s0022-3697(97)00150-9Pinquier, C., Demangeot, F., Frandon, J., Chervin, J.-C., Polian, A., Couzinet, B., … Maleyre, B. (2006). Raman scattering study of wurtzite and rocksalt InN under high pressure. Physical Review B, 73(11). doi:10.1103/physrevb.73.115211Ibáñez, J., Manjón, F. J., Segura, A., Oliva, R., Cuscó, R., Vilaplana, R., … Artús, L. (2011). High-pressure Raman scattering in wurtzite indium nitride. Applied Physics Letters, 99(1), 011908. doi:10.1063/1.3609327Li, S. X., Wu, J., Haller, E. E., Walukiewicz, W., Shan, W., Lu, H., & Schaff, W. J. (2003). Hydrostatic pressure dependence of the fundamental bandgap of InN and In-rich group III nitride alloys. Applied Physics Letters, 83(24), 4963-4965. doi:10.1063/1.1633681Franssen, G., Gorczyca, I., Suski, T., Kamińska, A., Pereiro, J., Muñoz, E., … Svane, A. (2008). Bowing of the band gap pressure coefficient in InxGa1−xN alloys. Journal of Applied Physics, 103(3), 033514. doi:10.1063/1.2837072Kamińska, A., Franssen, G., Suski, T., Gorczyca, I., Christensen, N. E., Svane, A., … Georgakilas, A. (2007). Role of conduction-band filling in the dependence of InN photoluminescence on hydrostatic pressure. Physical Review B, 76(7). doi:10.1103/physrevb.76.075203Shan, W., Walukiewicz, W., Haller, E. E., Little, B. D., Song, J. J., McCluskey, M. D., … Stall, R. A. (1998). Optical properties of InxGa1−xN alloys grown by metalorganic chemical vapor deposition. Journal of Applied Physics, 84(8), 4452-4458. doi:10.1063/1.368669Millot, M., Geballe, Z. M., Yu, K. M., Walukiewicz, W., & Jeanloz, R. (2012). Red-green luminescence in indium gallium nitride alloys investigated by high pressure optical spectroscopy. Applied Physics Letters, 100(16), 162103. doi:10.1063/1.4704367Franssen, G., Suski, T., Perlin, P., Teisseyre, H., Khachapuridze, A., Dmowski, L. H., … Schaff, W. (2006). Band-to-band character of photoluminescence from InN and In-rich InGaN revealed by hydrostatic pressure studies. Applied Physics Letters, 89(12), 121915. doi:10.1063/1.2356994Ibáñez, J., Segura, A., Manjón, F. J., Artús, L., Yamaguchi, T., & Nanishi, Y. (2010). Electronic structure of wurtzite and rocksalt InN investigated by optical absorption under hydrostatic pressure. Applied Physics Letters, 96(20), 201903. doi:10.1063/1.3431291Cuscó, R., Ibáñez, J., Alarcón-Lladó, E., Artús, L., Yamaguchi, T., & Nanishi, Y. (2009). Raman scattering study of the long-wavelength longitudinal-optical-phonon–plasmon coupled modes in high-mobility InN layers. Physical Review B, 79(15). doi:10.1103/physrevb.79.155210Cuscó, R., Alarcón-Lladó, E., Ibáñez, J., Yamaguchi, T., Nanishi, Y., & Artús, L. (2009). Raman scattering study of background electron density in InN: a hydrodynamical approach to the LO-phonon–plasmon coupled modes. Journal of Physics: Condensed Matter, 21(41), 415801. doi:10.1088/0953-8984/21/41/415801Syassen, K. (2008). Ruby under pressure. High Pressure Research, 28(2), 75-126. doi:10.1080/08957950802235640Wu, J., Walukiewicz, W., Shan, W., Yu, K. M., Ager, J. W., Li, S. X., … Schaff, W. J. (2003). Temperature dependence of the fundamental band gap of InN. Journal of Applied Physics, 94(7), 4457-4460. doi:10.1063/1.1605815Wu, J., Walukiewicz, W., Li, S. X., Armitage, R., Ho, J. C., Weber, E. R., … Jakiela, R. (2004). Effects of electron concentration on the optical absorption edge of InN. Applied Physics Letters, 84(15), 2805-2807. doi:10.1063/1.1704853Wu, J., Walukiewicz, W., Shan, W., Yu, K. M., Ager, J. W., Haller, E. E., … Schaff, W. J. (2002). Effects of the narrow band gap on the properties of InN. Physical Review B, 66(20). doi:10.1103/physrevb.66.201403Rinke, P., Winkelnkemper, M., Qteish, A., Bimberg, D., Neugebauer, J., & Scheffler, M. (2008). Consistent set of band parameters for the group-III nitrides AlN, GaN, and InN. Physical Review B, 77(7). doi:10.1103/physrevb.77.075202Furthmüller, J., Hahn, P. H., Fuchs, F., & Bechstedt, F. (2005). Band structures and optical spectra of InN polymorphs: Influence of quasiparticle and excitonic effects. Physical Review B, 72(20). doi:10.1103/physrevb.72.205106Serrano, J., Rubio, A., Hernández, E., Muñoz, A., & Mujica, A. (2000). Theoretical study of the relative stability of structural phases in group-III nitrides at high pressures. Physical Review B, 62(24), 16612-16623. doi:10.1103/physrevb.62.16612Christensen, N. E., & Gorczyca, I. (1994). Optical and structural properties of III-V nitrides under pressure. Physical Review B, 50(7), 4397-4415. doi:10.1103/physrevb.50.4397Duan, M.-Y., He, L., Xu, M., Xu, M.-Y., Xu, S., & Ostrikov, K. (Ken). (2010). Structural, electronic, and optical properties of wurtzite and rocksalt InN under pressure. Physical Review B, 81(3). doi:10.1103/physrevb.81.03310

Pressure effects on the vibrational properties of alpha-Bi2O3: an experimental and theoretical study

We report an experimental and theoretical high-pressure study of the vibrational properties of synthetic monoclinic bismuth oxide (alpha-Bi2O3), also known as mineral bismite. The comparison of Raman scattering measurements and theoretical lattice-dynamics ab initio calculations is key to understanding the complex vibrational properties of bismite. On one hand, calculations help in the symmetry assignment of phonons and to discover the phonon interactions taking place in this low-symmetry compound, which shows considerable phonon anticrossings; and, on the other hand, measurements help to validate the accuracy of first-principles calculations relating to this compound. We have also studied the pressure-induced amorphization (PIA) of synthetic bismite occurring around 20 GPa and showed that it is reversible below 25 GPa. Furthermore, a partial temperature-induced recrystallization (TIR) of the amorphous sample can be observed above 20 GPa upon heating to 200 C, thus evidencing that PIA at room temperature occurs because of the inability of the a phase to undergo a phase transition to a high-pressure phase. Raman scattering measurements of the TIR sample at room temperature during pressure release have been performed. The interpretation of these results in the light of ab initio calculations of the candidate phases at high pressures has allowed us to tentatively attribute the TIR phase to the recently found high-pressure hexagonal HPC phase and to discuss its lattice dynamics.This work has been supported by Brazilian Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) under project 201050/2012-9, by Ministerio de Ciencia e Innovacion of Spain (MICINN) under the National Program of Materials (MAT2010-21270-C04-03/04) and the Consolider-Ingenio 2010 Program (MALTA CSD2007-0045) and by Generalitat Valenciana through projects GVA-ACOMP-2013-012 and Prometeo 2009/053.Pereira, ALJ.; Gomis, O.; Sans, JA.; Pellicer-Porres, J.; Manjón Herrera, FJ.; Beltran, A.; Rodríguez-Hernández, P.... (2014). Pressure effects on the vibrational properties of alpha-Bi2O3: an experimental and theoretical study. Journal of Physics: Condensed Matter. 26(22):225401-1-225401-15. https://doi.org/10.1088/0953-8984/26/22/225401S225401-1225401-15262

Structural and vibrational study of cubic Sb2O3 under high pressure

We report an experimental and theoretical study of antimony oxide (Sb 2O 3) in its cubic phase (senarmontite) under high pressure. X-ray diffraction and Raman scattering measurements up to 18 and 25 GPa, respectively, have been complemented with ab initio total-energy and lattice-dynamics calculations. X-ray diffraction measurements do not provide evidence of a space-group symmetry change in senarmontite up to 18 GPa. However, Raman scattering measurements evidence changes in the pressure coefficients of the Raman mode frequencies at 3.5 and 10 GPa, respectively. The behavior of the Raman modes with increasing pressure up to 25 GPa is fully reproduced by the lattice-dynamics calculations in cubic Sb 2O 3. Therefore, the combined analysis of both experiments and lattice-dynamics calculations suggest the occurrence of two isostructural phase transformations at 3.5 and 10 GPa, respectively. Total-energy calculations show that the isostructural phase transformations occur through local atomic displacements in which senarmontite loses its molecular character to become a three-dimensional solid. In addition, our calculations provide evidence that cubic senarmontite cannot undergo a phase transition to orthorhombic valentinite at high pressure, and that a phase transition to a ß-Bi 2O 3-type structure is possible above 25 GPa. © 2012 American Physical Society.Financial support from the Spanish Consolider Ingenio 2010 Program (Project No. CDS2007-00045) is acknowledged. The work was also supported by Spanish MICCIN under Projects No. CTQ2009-14596-C02-01 and No. MAT2010-21270-C04-01/04 as well as from Comunidad de Madrid and European Social Fund, S2009/PPQ-1551 4161893 (QUIMAPRES) and from Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia under projects UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11. Spanish Fundacio Bancaixa Project No. P1-1A2009-08 and Brazilian Capes/Fundacion Carolina (BEX 3939/10-3) are also acknowledged.Pereira, ALJ.; Gracia, L.; Santamaría-Pérez, D.; Vilaplana Cerda, RI.; Manjón Herrera, FJ.; Errandonea, D.; Nalin, M.... (2012). Structural and vibrational study of cubic Sb2O3 under high pressure. Physical Review B. 85(17):174108-1-174108-11. https://doi.org/10.1103/PhysRevB.85.174108S174108-1174108-118517Youk, J. H., Kambour, R. P., & MacKnight, W. J. (2000). Polymerization of Ethylene Terephthalate Cyclic Oligomers with Antimony Trioxide†. Macromolecules, 33(10), 3594-3599. doi:10.1021/ma991838dZabinski, J. S., Donley, M. S., & McDevitt, N. T. (1993). Mechanistic study of the synergism between Sb2O3 and MoS2 lubricant systems using Raman spectroscopy. Wear, 165(1), 103-108. doi:10.1016/0043-1648(93)90378-yGhosh, A., & Chakravorty, D. (1991). Transport properties of semiconducting CuO-Sb2O3-P2O5glasses. Journal of Physics: Condensed Matter, 3(19), 3335-3342. doi:10.1088/0953-8984/3/19/012Gopalakrishnan, P. S., & Manohar, H. (1975). Kinetics and mechanism of the transformation in antimony trioxide from orthorhombic valentinite to cubic senarmontite. Journal of Solid State Chemistry, 15(1), 61-67. doi:10.1016/0022-4596(75)90271-6Zachariasen, W. H. (1932). THE ATOMIC ARRANGEMENT IN GLASS. Journal of the American Chemical Society, 54(10), 3841-3851. doi:10.1021/ja01349a006Matsumoto, A., Koyama, Y., Togo, A., Choi, M., & Tanaka, I. (2011). Electronic structures of dynamically stable As2O3, Sb2O3, and Bi2O3crystal polymorphs. Physical Review B, 83(21). doi:10.1103/physrevb.83.214110Miller, P. J., & Cody, C. A. (1982). Infrared and Raman investigation of vitreous antimony trioxide. Spectrochimica Acta Part A: Molecular Spectroscopy, 38(5), 555-559. doi:10.1016/0584-8539(82)80146-3Svensson, C. (1975). Refinement of the crystal structure of cubic antimony trioxide, Sb2O3. Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, 31(8), 2016-2018. doi:10.1107/s0567740875006759Wood, C., van Pelt, B., & Dwight, A. (1972). The Optical Properties of Amorphous and Crystalline Sb2O3. Physica Status Solidi (b), 54(2), 701-706. doi:10.1002/pssb.2220540234Nalin, M., Messaddeq, Y., Ribeiro, S. J. L., Poulain, M., Briois, V., Brunklaus, G., … Eckert, H. (2004). Structural organization and thermal properties of the Sb2O3–SbPO4glass system. J. Mater. Chem., 14(23), 3398-3405. doi:10.1039/b406075jOrosel, D., Dinnebier, R. E., Blatov, V. A., & Jansen, M. (2012). Structure of a new high-pressure–high-temperature modification of antimony(III) oxide, γ-Sb2O3, from high-resolution synchrotron powder diffraction data. Acta Crystallographica Section B Structural Science, 68(1), 1-7. doi:10.1107/s0108768111046751Grzechnik, A. (1999). Compressibility and Vibrational Modes in Solid As4O6. Journal of Solid State Chemistry, 144(2), 416-422. doi:10.1006/jssc.1999.8189Soignard, E., Amin, S. A., Mei, Q., Benmore, C. J., & Yarger, J. L. (2008). High-pressure behavior ofAs2O3: Amorphous-amorphous and crystalline-amorphous transitions. Physical Review B, 77(14). doi:10.1103/physrevb.77.144113Chouinard, C., & Desgreniers, S. (1999). Bi2O3 under hydrostatic pressure: observation of a pressure-induced amorphization. Solid State Communications, 113(3), 125-129. doi:10.1016/s0038-1098(99)00463-9Geng, A., Cao, L., Wan, C., & Ma, Y. (2011). High-pressure Raman investigation of the semiconductor antimony oxide. physica status solidi (c), 8(5), 1708-1711. doi:10.1002/pssc.201000786Manjón, F. J., & Errandonea, D. (2009). Pressure-induced structural phase transitions in materials and earth sciences. physica status solidi (b), 246(1), 9-31. doi:10.1002/pssb.200844238Mao, H. K., Xu, J., & Bell, P. M. (1986). 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Unveiling the Chemical and Morphological Features of Sb−SnO2Nanocrystals by the Combined Use of High-Resolution Transmission Electron Microscopy and ab Initio Surface Energy Calculations. Journal of the American Chemical Society, 131(40), 14544-14548. doi:10.1021/ja905896uBecke, A. D. (1993). Density‐functional thermochemistry. III. The role of exact exchange. The Journal of Chemical Physics, 98(7), 5648-5652. doi:10.1063/1.464913Lee, C., Yang, W., & Parr, R. G. (1988). Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. Physical Review B, 37(2), 785-789. doi:10.1103/physrevb.37.785Beltrán, A., Gracia, L., & Andrés, J. (2006). Density Functional Theory Study of the Brookite Surfaces and Phase Transitions between Natural Titania Polymorphs. The Journal of Physical Chemistry B, 110(46), 23417-23423. doi:10.1021/jp0643000Grimme, S. (2006). Semiempirical GGA-type density functional constructed with a long-range dispersion correction. 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Physical Review B, 6(6), 2285-2291. doi:10.1103/physrevb.6.2285Chefki, M., Abd-Elmeguid, M. M., Micklitz, H., Huhnt, C., Schlabitz, W., Reehuis, M., & Jeitschko, W. (1998). Pressure-induced Transition of the Sublattice Magnetization inEuCo2P2: Change from Local MomentEu(4f)to ItinerantCo(3d)Magnetism. Physical Review Letters, 80(4), 802-805. doi:10.1103/physrevlett.80.802Caracas, R., & Gonze, X. (2004). Structural, electronic, and dynamical properties of calaveriteAuTe2under pressure. Physical Review B, 69(14). doi:10.1103/physrevb.69.144114Svane, A., Strange, P., Temmerman, W. M., Szotek, Z., Winter, H., & Petit, L. (2001). Pressure-Induced Valence Transitions in Rare Earth Chalcogenides and Pnictides. physica status solidi (b), 223(1), 105-116. doi:10.1002/1521-3951(200101)223:13.0.co;2-iYoo, C. S., Maddox, B., Klepeis, J.-H. P., Iota, V., Evans, W., McMahan, A., … Pickett, W. E. (2005). First-Order Isostructural Mott Transition in Highly Compressed MnO. Physical Review Letters, 94(11). doi:10.1103/physrevlett.94.115502Rosner, H., Koudela, D., Schwarz, U., Handstein, A., Hanfland, M., Opahle, I., … Richter, M. (2006). Magneto-elastic lattice collapse in YCo5. Nature Physics, 2(7), 469-472. doi:10.1038/nphys341Polian, A., Gauthier, M., Souza, S. M., Trichês, D. M., Cardoso de Lima, J., & Grandi, T. A. (2011). Two-dimensional pressure-induced electronic topological transition in Bi2Te3. Physical Review B, 83(11). doi:10.1103/physrevb.83.113106Vilaplana, R., Gomis, O., Manjón, F. J., Segura, A., Pérez-González, E., Rodríguez-Hernández, P., … Kucek, V. (2011). High-pressure vibrational and optical study of Bi2Te3. Physical Review B, 84(10). doi:10.1103/physrevb.84.104112Vilaplana, R., Santamaría-Pérez, D., Gomis, O., Manjón, F. J., González, J., Segura, A., … Kucek, V. (2011). Structural and vibrational study of Bi2Se3under high pressure. 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High-pressure lattice dynamics in wurtzite and rocksalt indium nitride investigated by means of Raman spectroscopy

We present an experimental and theoretical lattice-dynamical study of InN at high hydrostatic pressures. We perform Raman scattering measurements on five InN epilayers, with different residual strain and free electron concentrations. The experimental results are analyzed in terms of ab initio lattice-dynamical calculations on both wurtzite InN (w-InN) and rocksalt InN (rs-InN) as a function of pressure. Experimental and theoretical pressure coefficients of the optical modes in w-InN are compared, and the role of residual strain on the measured pressure coefficients is analyzed. In the case of the LO band, we analyze and discuss its pressure behavior considering the double-resonance mechanism responsible for the selective excitation of LO phonons with large wave vectors in w-InN. The pressure behavior of the L− coupled mode observed in a heavily doped n-type sample allows us to estimate the pressure dependence of the electron effective mass in w-InN. The results thus obtained are in good agreement with k⋅p theory. The wurtzite-to-rocksalt phase transition on the upstroke cycle and the rocksalt-to-wurtzite backtransition on the downstroke cycle are investigated, and the Raman spectra of both phases are interpreted in terms of DFT lattice-dynamical calculations. ©2013 American Physical SocietyWork was supported by the Spanish Ministerio de Economia y Competitividad through Projects MAT2010-16116, MAT2010-21270-C04-04 and MALTA Consolider Ingenio 2010 (CSD2007-00045).Ibánez, J.; Oliva, R.; Manjón Herrera, FJ.; Segura, A.; Yamaguchi, T.; Nanishi, Y.; Cuscó, R.... (2013). High-pressure lattice dynamics in wurtzite and rocksalt indium nitride investigated by means of Raman spectroscopy. Physical Review B. 88:115202-1-115202-13. https://doi.org/10.1103/PhysRevB.88.115202S115202-1115202-1388Wu, J. (2009). When group-III nitrides go infrared: New properties and perspectives. Journal of Applied Physics, 106(1), 011101. doi:10.1063/1.3155798Pinquier, C., Demangeot, F., Frandon, J., Pomeroy, J. W., Kuball, M., Hubel, H., … Gil, B. (2004). Raman scattering in hexagonal InN under high pressure. Physical Review B, 70(11). doi:10.1103/physrevb.70.113202Pinquier, C., Demangeot, F., Frandon, J., Chervin, J.-C., Polian, A., Couzinet, B., … Maleyre, B. (2006). Raman scattering study of wurtzite and rocksalt InN under high pressure. Physical Review B, 73(11). doi:10.1103/physrevb.73.115211Yao, L. D., Luo, S. D., Shen, X., You, S. J., Yang, L. X., Zhang, S. J., … Xie, S. S. (2010). Structural stability and Raman scattering of InN nanowires under high pressure. Journal of Materials Research, 25(12), 2330-2335. doi:10.1557/jmr.2010.0290Ibáñez, J., Manjón, F. J., Segura, A., Oliva, R., Cuscó, R., Vilaplana, R., … Artús, L. (2011). High-pressure Raman scattering in wurtzite indium nitride. Applied Physics Letters, 99(1), 011908. doi:10.1063/1.3609327Uehara, S., Masamoto, T., Onodera, A., Ueno, M., Shimomura, O., & Takemura, K. (1997). Equation of state of the rocksalt phase of III–V nitrides to 72 GPa or higher. Journal of Physics and Chemistry of Solids, 58(12), 2093-2099. doi:10.1016/s0022-3697(97)00150-9Duan, M.-Y., He, L., Xu, M., Xu, M.-Y., Xu, S., & Ostrikov, K. (Ken). (2010). Structural, electronic, and optical properties of wurtzite and rocksalt InN under pressure. Physical Review B, 81(3). doi:10.1103/physrevb.81.033102Davydov, V. Y., Klochikhin, A. A., Smirnov, A. N., Strashkova, I. Y., Krylov, A. S., Lu, H., … Gwo, S. (2009). Selective excitation ofE1(LO)andA1(LO)phonons with large wave vectors in the Raman spectra of hexagonal InN. Physical Review B, 80(8). doi:10.1103/physrevb.80.081204Cuscó, R., Ibáñez, J., Alarcón-Lladó, E., Artús, L., Yamaguchi, T., & Nanishi, Y. (2009). Raman scattering study of the long-wavelength longitudinal-optical-phonon–plasmon coupled modes in high-mobility InN layers. Physical Review B, 79(15). doi:10.1103/physrevb.79.155210Ernst, S., Goñi, A. R., Syassen, K., & Cardona, M. (1995). LO-Phonon-plasmon modes in n-GaAs and n-InP under pressure. Journal of Physics and Chemistry of Solids, 56(3-4), 567-570. doi:10.1016/0022-3697(94)00242-8Ernst, S., Goñi, A. R., Syassen, K., & Cardona, M. (1996). Plasmon Raman scattering and photoluminescence of heavily dopedn-type InP near the Γ-X crossover. Physical Review B, 53(3), 1287-1293. doi:10.1103/physrevb.53.1287Lin, Y. C., Chiu, C. H., Fan, W. C., Chia, C. H., Yang, S. L., Chuu, D. S., … Chou, W. C. (2007). Raman scattering of longitudinal-optical-phonon-plasmon coupling in Cl-doped ZnSe under high pressure. Journal of Applied Physics, 102(12), 123510. doi:10.1063/1.2826936Gonze, X., Beuken, J.-M., Caracas, R., Detraux, F., Fuchs, M., Rignanese, G.-M., … Allan, D. C. (2002). 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Physical Review B, 49(1), 14-21. doi:10.1103/physrevb.49.14Serrano, J., Bosak, A., Krisch, M., Manjón, F. J., Romero, A. H., Garro, N., … Kuball, M. (2011). InN Thin Film Lattice Dynamics by Grazing Incidence Inelastic X-Ray Scattering. Physical Review Letters, 106(20). doi:10.1103/physrevlett.106.205501Giannozzi, P., de Gironcoli, S., Pavone, P., & Baroni, S. (1991). Ab initiocalculation of phonon dispersions in semiconductors. Physical Review B, 43(9), 7231-7242. doi:10.1103/physrevb.43.7231Gonze, X., & Lee, C. (1997). Dynamical matrices, Born effective charges, dielectric permittivity tensors, and interatomic force constants from density-functional perturbation theory. Physical Review B, 55(16), 10355-10368. doi:10.1103/physrevb.55.10355Weinstein, B. A. (1977). Phonon dispersion of zinc chalcogenides under extreme pressure and the metallic transformation. Solid State Communications, 24(9), 595-598. doi:10.1016/0038-1098(77)90369-6Yakovenko, E. V., Gauthier, M., & Polian, A. (2004). High-pressure behavior of the bond-bending mode of AIN. Journal of Experimental and Theoretical Physics, 98(5), 981-985. doi:10.1134/1.1767565Ibáñez, J., Segura, A., García-Domene, B., Oliva, R., Manjón, F. J., Yamaguchi, T., … Artús, L. (2012). High-pressure optical absorption in InN: Electron density dependence in the wurtzite phase and reevaluation of the indirect band gap of rocksalt InN. Physical Review B, 86(3). doi:10.1103/physrevb.86.035210Serrano, J., Romero, A. H., Manjón, F. J., Lauck, R., Cardona, M., & Rubio, A. (2004). Pressure dependence of the lattice dynamics of ZnO: Anab initioapproach. Physical Review B, 69(9). doi:10.1103/physrevb.69.094306Cuscó, R., Ibáñez, J., Domenech-Amador, N., Artús, L., Zúñiga-Pérez, J., & Muñoz-Sanjosé, V. (2010). Raman scattering of cadmium oxide epilayers grown by metal-organic vapor phase epitaxy. Journal of Applied Physics, 107(6), 063519. doi:10.1063/1.3357377Cuscó, R., Alarcón-Lladó, E., Ibáñez, J., Yamaguchi, T., Nanishi, Y., & Artús, L. (2009). Raman scattering study of background electron density in InN: a hydrodynamical approach to the LO-phonon–plasmon coupled modes. Journal of Physics: Condensed Matter, 21(41), 415801. doi:10.1088/0953-8984/21/41/415801Cuscó, R., Ibáñez, J., Alarcón-Lladó, E., Artús, L., Yamaguchi, T., & Nanishi, Y. (2009). Photoexcited carriers and surface recombination velocity in InN epilayers: A Raman scattering study. Physical Review B, 80(15). doi:10.1103/physrevb.80.155204Wang, X., Che, S.-B., Ishitani, Y., & Yoshikawa, A. (2006). Experimental determination of strain-free Raman frequencies and deformation potentials for the E2 high and A1(LO) modes in hexagonal InN. Applied Physics Letters, 89(17), 171907. doi:10.1063/1.2364884Perlin, P., Jauberthie-Carillon, C., Itie, J. P., San Miguel, A., Grzegory, I., & Polian, A. (1992). Raman scattering and x-ray-absorption spectroscopy in gallium nitride under high pressure. Physical Review B, 45(1), 83-89. doi:10.1103/physrevb.45.83Perlin, P., Suski, T., Ager, J. W., Conti, G., Polian, A., Christensen, N. E., … Haller, E. E. (1999). Transverse effective charge and its pressure dependence in GaN single crystals. Physical Review B, 60(3), 1480-1483. doi:10.1103/physrevb.60.1480Halsall, M. P., Harmer, P., Parbrook, P. J., & Henley, S. J. (2004). Raman scattering and absorption study of the high-pressure wurtzite to rocksalt phase transition of GaN. Physical Review B, 69(23). doi:10.1103/physrevb.69.235207Goñi, A. R., Siegle, H., Syassen, K., Thomsen, C., & Wagner, J.-M. (2001). Effect of pressure on optical phonon modes and transverse effective charges inGaNandAlN. Physical Review B, 64(3). doi:10.1103/physrevb.64.035205Watson, G. H., Daniels, W. B., & Wang, C. S. (1981). Measurements of Raman intensities and pressure dependence of phonon frequencies in sapphire. 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Physical Review B, 71(11). doi:10.1103/physrevb.71.115203Inushima, T., Higashiwaki, M., & Matsui, T. (2003). Optical properties of Si-doped InN grown on sapphire (0001). Physical Review B, 68(23). doi:10.1103/physrevb.68.235204Kasic, A., Valcheva, E., Monemar, B., Lu, H., & Schaff, W. J. (2004). InNdielectric function from the midinfrared to the ultraviolet range. Physical Review B, 70(11). doi:10.1103/physrevb.70.115217Wu, J., Walukiewicz, W., Shan, W., Yu, K. M., Ager, J. W., Haller, E. E., … Schaff, W. J. (2002). Effects of the narrow band gap on the properties of InN. Physical Review B, 66(20). doi:10.1103/physrevb.66.201403Kim, J. G., Kamei, Y., Hasuike, N., Harima, H., Kisoda, K., Sasamoto, K., & Yamamoto, A. (2010). Effective mass of InN estimated by Raman scattering. physica status solidi (c), 7(7-8), 1887-1889. doi:10.1002/pssc.200983567Christensen, N. E., & Gorczyca, I. (1994). Optical and structural properties of III-V nitrides under pressure. 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High-pressure Raman scattering in wurtzite indium nitride

Copyright (2011) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.We perform Raman-scattering measurements at high hydrostatic pressures on c-face and a-face InN layers to investigate the high-pressure behavior of the zone-center optical phonons of wurtzite InN. Linear pressure coefficients and mode Grneisen parameters are obtained, and the experimental results are compared with theoretical values obtained from ab initio lattice-dynamical calculations. Good agreement is found between the experimental and calculated results. © 2011 American Institute of Physics.Work supported by the Spanish MICINN (Projects MAT2010-16116, MAT2008-06873-C02-02, MAT2010-21270-C04-04, and CSD2007-00045), the Catalan Government (BE-DG 2009), and the Spanish Council for Research (PIE2009-CSIC).Ibanez, J.; Manjón Herrera, FJ.; Segura, A.; Oliva, R.; Cusco, R.; Vilaplana Cerda, RI.; Yamaguchi, T.... (2011). High-pressure Raman scattering in wurtzite indium nitride. Applied Physics Letters. 99:119081-119083. https://doi.org/10.1063/1.3609327S11908111908399Veal, T., McConville, C., & Schaff, W. (Eds.). (2009). Indium Nitride and Related Alloys. doi:10.1201/9781420078107Gallinat, C. S., Koblmüller, G., Brown, J. S., Bernardis, S., Speck, J. S., Chern, G. D., … Wraback, M. (2006). In-polar InN grown by plasma-assisted molecular beam epitaxy. Applied Physics Letters, 89(3), 032109. doi:10.1063/1.2234274Li, S. X., Wu, J., Haller, E. E., Walukiewicz, W., Shan, W., Lu, H., & Schaff, W. J. (2003). Hydrostatic pressure dependence of the fundamental bandgap of InN and In-rich group III nitride alloys. Applied Physics Letters, 83(24), 4963-4965. doi:10.1063/1.1633681Gorczyca, I., Plesiewicz, J., Dmowski, L., Suski, T., Christensen, N. E., Svane, A., … Speck, J. S. (2008). Electronic structure and effective masses of InN under pressure. Journal of Applied Physics, 104(1), 013704. doi:10.1063/1.2953094Domènech-Amador, N., Cuscó, R., Artús, L., Yamaguchi, T., & Nanishi, Y. (2011). Raman scattering study of anharmonic phonon decay in InN. Physical Review B, 83(24). doi:10.1103/physrevb.83.245203Serrano, J., Bosak, A., Krisch, M., Manjón, F. J., Romero, A. H., Garro, N., … Kuball, M. (2011). InN Thin Film Lattice Dynamics by Grazing Incidence Inelastic X-Ray Scattering. Physical Review Letters, 106(20). doi:10.1103/physrevlett.106.205501Pinquier, C., Demangeot, F., Frandon, J., Pomeroy, J. W., Kuball, M., Hubel, H., … Gil, B. (2004). Raman scattering in hexagonal InN under high pressure. Physical Review B, 70(11). doi:10.1103/physrevb.70.113202Pinquier, C., Demangeot, F., Frandon, J., Chervin, J.-C., Polian, A., Couzinet, B., … Maleyre, B. (2006). Raman scattering study of wurtzite and rocksalt InN under high pressure. Physical Review B, 73(11). doi:10.1103/physrevb.73.115211Yao, L. D., Luo, S. D., Shen, X., You, S. J., Yang, L. X., Zhang, S. J., … Xie, S. S. (2010). Structural stability and Raman scattering of InN nanowires under high pressure. Journal of Materials Research, 25(12), 2330-2335. doi:10.1557/jmr.2010.0290Cuscó, R., Ibáñez, J., Alarcón-Lladó, E., Artús, L., Yamaguchi, T., & Nanishi, Y. (2009). Raman scattering study of the long-wavelength longitudinal-optical-phonon–plasmon coupled modes in high-mobility InN layers. Physical Review B, 79(15). doi:10.1103/physrevb.79.155210Wagner, J.-M., & Bechstedt, F. (2003). First-principles study of phonon-mode softening under pressure: the case of GaN and AlN. physica status solidi (b), 235(2), 464-469. doi:10.1002/pssb.200301603Weinstein, B. A. (1977). Phonon dispersion of zinc chalcogenides under extreme pressure and the metallic transformation. Solid State Communications, 24(9), 595-598. doi:10.1016/0038-1098(77)90369-6Yakovenko, E. V., Gauthier, M., & Polian, A. (2004). High-pressure behavior of the bond-bending mode of AIN. Journal of Experimental and Theoretical Physics, 98(5), 981-985. doi:10.1134/1.1767565Reparaz, J. S., Muniz, L. R., Wagner, M. R., Goñi, A. R., Alonso, M. I., Hoffmann, A., & Meyer, B. K. (2010). Reduction of the transverse effective charge of optical phonons in ZnO under pressure. Applied Physics Letters, 96(23), 231906. doi:10.1063/1.3447798Perlin, P., Jauberthie-Carillon, C., Itie, J. P., San Miguel, A., Grzegory, I., & Polian, A. (1992). Raman scattering and x-ray-absorption spectroscopy in gallium nitride under high pressure. Physical Review B, 45(1), 83-89. doi:10.1103/physrevb.45.83Manjón, F. J., Errandonea, D., Romero, A. H., Garro, N., Serrano, J., & Kuball, M. (2008). Lattice dynamics of wurtzite and rocksalt AlN under high pressure: Effect of compression on the crystal anisotropy of wurtzite-type semiconductors. Physical Review B, 77(20). doi:10.1103/physrevb.77.205204Jephcoat, A. P., Hemley, R. J., Mao, H. K., Cohen, R. E., & Mehl, M. J. (1988). Raman spectroscopy and theoretical modeling of BeO at high pressure. Physical Review B, 37(9), 4727-4734. doi:10.1103/physrevb.37.4727Ibáñez, J., Segura, A., Manjón, F. J., Artús, L., Yamaguchi, T., & Nanishi, Y. (2010). Electronic structure of wurtzite and rocksalt InN investigated by optical absorption under hydrostatic pressure. Applied Physics Letters, 96(20), 201903. doi:10.1063/1.3431291Goñi, A. R., Siegle, H., Syassen, K., Thomsen, C., & Wagner, J.-M. (2001). Effect of pressure on optical phonon modes and transverse effective charges inGaNandAlN. Physical Review B, 64(3). doi:10.1103/physrevb.64.03520