Abstract
A synthetic clinopyroxene with composition LiFe3+Ge2O6, monoclinic s.g. P21/c, a = 9.8792(7), b = 8.8095(5), c = 5.3754(3) Å, β = 108.844(6)°, V = 442.75(16) Å3, has been studied by in situ low- and high-temperature single-crystal X-ray diffraction. The variation of lattice parameters and the intensity of the b-type reflections (h + k = 2n + 1, only present in the P-symmetry) with increasing temperature showed a displacive phase transition from space group P21/c to C2/c at a transition temperature T tr = 789 K, first order in character, with a sudden volume increase of 1.6% and a decrease of β by 1° at the transition. This spontaneous dilatation is reversible, shows a limited hysteresis of ±10°C, and corresponds to the vanishing of the b-type reflections, thus indicating a symmetry increase to space group C2/c. Below T tr an expansion is observed for all the cell parameters, while the β angle remained almost constant; at T > T tr the thermal volume expansion is due to dilatation of the structure in the \((\bar{1}\,0\,1) \) plane, mostly along [0 1 0], and pure shear in the (0 1 0) plane due to the decrease of β. From comparison with silicate analogues, the germanate clinopyroxenes are more expansible, while the P21/c expands more than the C2/c phase. The evolution of Q 2 (calculated as the normalized intensity of b-type reflections) with T in the framework of the Landau theory has been done using a standard expression for a first order phase transition. We observe a jump of Q 20 = 0.538(2) at T tr, with T c of 481(7) K, b/a = −2,290 K, and c/a = 3,192 K, and thus far from being tri-critical point. A closely related composition (LiFe3+Si2O6) shows an equivalent phase transition at 228 K, which is very close to the tri-critical point and 561 K cooler. This result indicates that a change in the composition of tetrahedral sites can have dramatic effects on the P21/c ↔ C2/c displacive phase transition in clinopyroxenes. The major changes observed in the evolution of the crystal structure with T are observed in the M2 polyhedron, with a volume decrease by ca. 13.3%, compared to ca. 1.3% observed in the M1 polyhedron. The tetrahedra behave as rigid units with neither a significant change of volume at T > T tr (<1‰), nor a change of tilting of the basal plane. No change in coordination is observed at T > T tr in the M2 polyhedron, which remains sixfold coordinated although a strong deformation of this polyhedron is observed. This deformation is related to a strong change by 51.4° at T tr of the kinking angle (O3–O3–O3 angle) of the B-chain of tetrahedra, which switches from O-rotated to S-rotated [from 143.3(5)° to 194.7(6)°]. The A-chain is S-rotated at T < T tr [206.8(5)° at 703 K] and extends by 12° at the transition.
Similar content being viewed by others
References
Arlt T, Angel RJ (2000) Displacive phase transition in C-centred clinopyroxenes: spodumene, LiScSi2O6 and ZnSiO3. Phys Chem Min 27:719–731
Arlt T, Armbruster T (1997) The temperature-dependent P21/c ↔ C2/c phase transition in the clinopyroxene kanoite MnMg[Si2O6]; a single-crystal X-ray and optical study. Eur J Mineral 9:953–964
Arlt T, Kunz M, Stolz J, Armbruster T, Angel RJ (2000) P-T-X data on P21/c-clinopyroxenes and their displacive phase transitions. Contrib Mineral Petrol 138:35–45
Bartelmehs KL, Downs RT, Gibbs GV, Boisen MB Jr, Birch JB (1995) Tetrahedral rigid-body motion in silicates. Am Mineral 80:680–690
Behruzi M, Hahn T, Prewitt CT, Baldwin K (1984) Low- and high-temperature crystal structures of LiFeGe2O6, LiFeSi2O6 and LiCrSi2O6. Acta Crystallogr A 40(Suppl C):247
Blessing RH, Coppens P, Becker P (1974) Computer analysis of step scanned X-ray data. J Appl Crystalogr 7:488–492
Brown ID (1981) The bond-valence method: an empirical approach to chemical structure and bonding. In: O’Keeffe M, Navrotsky A (eds) Structure and bonding in crystals II. Academic Press, New York, pp 1–30
Bruce AD, Cowley RA (1981) Structural phase transitions. Taylor and Francis, London, p 326
Bruker-Nonius (2004) APEX2: software suite for data collection and processing of single crystal X-ray diffraction data. Bruker AXS Inc, Madison
Cámara F, Carpenter MA, Domeneghetti MC, Tazzoli V (2002) Non-convergent ordering and displacive phase transition in pigeonite: in situ HT XRD study. Phys Chem Miner 29:331–340
Cámara F, Iezzi G, Oberti R (2003a) HT-XRD study of synthetic ferrian magnesian spodumene: the effect of site dimension on the P21/c ↔ C2/c phase transition. Phys Chem Miner 30:20–30
Cámara F, Carpenter MA, Domeneghetti MC, Tazzoli V (2003b) Coupling between non-convergent ordering and transition temperature in the C2/c ↔ P21/c phase transition in pigeonite. Am Mineral 88:1115–1128
Cámara F, Nestola F, Angel RJ, Ohashi H (2009) Spontaneous strain variations through the low-temperature displacive phase transition of LiGaSi2O6 clinoyproxene. Eur J Mineral 21:599–614
Cameron M, Papike JJ (1981) Structural and chemical variations in pyroxenes. Am Mineral 66:1–50
Cameron M, Sueno S, Prewitt CT, Papike JJ (1973) High-temperature crystal chemistry of acmite, diopside, hedenbergite, spodumene and ureite. Am Mineral 58:594–618
Carpenter MA, Salje EKH, Graeme-Barber A (1998) Spontaneous strain as a determinant of thermodynamic properties for phase transition in minerals. Eur J Mineral 10:621–691
Clark JR, Appleman DE, Papike JJ (1969) Crystal chemical characterization pf clino-pyroxenes based on eight new structure refinements. Mineral Soc Am Spec Pap 2:31–50
Downs RT (2005) XtalDraw for Windows Commission on Powder Diffraction. IUCr Newslett 30:32–33
Farrugia L (1999) WinGX suite for small-molecule single-crystal crystallography. J Appl Crystallogr 32:837–838
Hawthorne FC, Ungaretti L, Oberti R (1995) Site populations in minerals: terminology and presentation of results of crystal structure refinement. Can Mineral 33:907–911
Hugh-Jones D (1997) Thermal expansion of MgSiO3 and FeSiO3 ortho- and clinopyroxens. Am Mineral 82:689–696
Knight KS (1996) A neutron powder diffraction determination of the thermal expansion tensor of crocoite (PbCrO4) between 60 and 290 K. Min Mag 60:963–972
Knight KS, Stretton IC, Schonfield PF (1999) Temperature evolution between 50 K and 320 K of the thermal expansion tensor of gypsum derived from neutron powder diffraction data. Phys Chem Miner 26:477–483
Lehmann MS, Larsen FK (1974) A method for location of the peaks in step-scan-measured Bragg reflections. Acta Crystallogr A30:580–584
Levien L, Prewitt CT (1981) High pressure structural study of diopside. Am Mineral 66:315–323
Nestola F, Gatta DG, Boffa Ballaran T (2006) The effect of Ca substitution on the elastic and structural behaviour of orthoenstatite. Am Mineral 91:809–815
Nestola F, Boffa Ballaran T, Ohashi H (2008a) The high-pressure C2/c-P21/c phase transition along the LiAlSi2O6-LiGaSi2O6 solid solution. Phys Chem Miner 35:477–484
Nestola F, Boffa Ballaran T, Liebske C, Thompson R, Downs RT (2008b) The effect of the hedenbergitic substitution on the compressibility of jadeite. Am Mineral 93:1005–1013
Nestola F, Redhammer GJ, Pamato MG, Secco L, Dal Negro A (2009) High-pressure phase transformation in LiFeGe2O6 pyroxene. Am Mineral 94:616–621
North ACT, Phillips DC, Mathews FS (1968) A semi-empirical method of absorption correction. Acta Crystallogr A24:351–359
Ohashi H, Osawa T, Sato A (2003) Crystal structures of Li(Al, Ga)Si2O6 pyroxenes. In: Ohashi H (ed) X-ray study on Si–O bonding. Maruzen Publishing Service Center, Tokyo, pp 146–158
Pachler A (2009) Strukturelle Phasenbeziehungen in (Na,Li)M2(Fe,Cr)M1Ge2O6 Klinopyroxenen als Funktion von XLi und T. Master Thesis, University of Salzburg
Pommier CJS, Downs RT, Stimpfl M, Redhammer GJ, Denton MB (2005) Raman and X-ray investigations of LiFeSi2O6 pyroxene under pressure. J Raman Spectr 36:864–871
Redhammer GJ, Roth G (2004) Structural changes upon the temperature dependent C2/c → P21/c phase transition in LiMe3+Si2O6 clinopyroxenes, Me = Cr, Ga, Fe, V and Sc. Z Krist 219(10):585–605
Redhammer GJ, Roth G, Paulus W, André G, Lottermoser W, Amthauer G, Treutmann W, Koppelhuber-Bitschnau B (2001) Crystal and magnetic structure of Li-Aegirine LiFe3+Si2O6: a temperature dependent study. Phys Chem Miner 28:337–346
Redhammer GJ, Amthauer G, Roth G, Tippelt G, Lottermoser W (2006) Single crystal X-ray diffraction and temperature dependent 57Fe Mössbauer spectroscopy on the hedenbergite–aegirine (Ca, Na)(Fe2+, Fe3+)Si2O6 solid solution. Am Mineral 91:1271–1292
Redhammer GJ, Roth G, Treutmann W, Hoelzel M, Paulus W, André G, Pietzonka C, Amthauer G (2009) The magnetic structure of clinopyroxene-type LiFeGe2O6 and revised data on multiferroic LiFeSi2O6. J Solid State Chem 182:2374–2384
Redhammer GJ, Senyshin A, Tippelt G, Pietzonka C, Roth G, Amthauer G (2010) Magnetic and nuclear structure and thermal expansion of orthorhombic and monoclinic polymorphs of CoGeO3 pyroxene. Phys Chem Min. doi:10.1007/s00269-009-0335-x)
Renner B, Lehmann G (1986) Correlation of angular and bond lengths distortion in TO4 units in crystals. Z Krist 175:43–59
Robinson K, Gibbs GV, Ribbe PH (1971) Quadratic elongation, a quantitative measure of distrotion in polyhedra. Science 172:567–570
Rodríguez-Carvajal J (2001) Recent developments of the program. In: Commission on powder diffraction (IUCr). Newsletter 26:12–19. http://journals.iucr.org/iucr-top/comm/cpd/Newsletters/
Ross NL, Navrotsky A (1988) Study of MgGeO3 polymorphs (orthopyroxene, clinopyroxene, and ilmenite structures) by calorimetry, spectroscopy and phase equilibria. Am Mineral 73:1355–1365
Schlenker JL, Gibbs GV, Boisen MB Jr (1975) Thermal expansion coefficients for monoclinic crystals: a phenomenological approach. Am Min 60:828–833
Schomaker V, Trueblood KN (1968) On the rigid-body motion of molecules in crystals. Acta Crystallogr B24:63–76
Schonfield PF, Knight KS, van der Houwen JAM, Valsami-Jones E (2004) The role of hydrogen bonding in the thermal expansion and dehydration of brushite, di-calcium phosphate dihydrate. Phys Chem Miner 31:606–624
Sheldrick GM (2008) A short history of SHELX. Acta Cryst A64:112–122
Stoe & Cie (1996) X-Shape and X-Red. Stoe & Cie Inc. Darmstadt, Germany
Thompson RM, Downs RT (2007) The crystal structure of diopside at pressure to 10 GPa. Am Mineral 93:177–186
Tribaudino M, Nestola F, Cámara F, Domeneghetti MC (2002) The high-temperature P21/c ↔ C2/c phase transition in Fe-free pyroxene (Ca0.15Mg1.85Si2O6): structural and thermodynamic behavior. Am Mineral 87:648–657
Tribaudino M, Nestola F, Prencipe M, Rundolf H (2003) A single-crystal neutron diffraction investigation of spodumene at 54 K. Can Mineral 41:521–527
Tribaudino M, Nestola F, Ohashi H (2005) High temperature single crystal investigation in a clinopyroxen of composition (Na0.5Ca0.5)(Cr0.5Mg0.5)Si2O6. Eur J Mineral 17:297–304
Tribaudino M, Nestola F, Bruno M, Boffa Ballaran T, Liebske C (2008) Thermal expansion along the NaAlSi2O6–NaFe3+Si2O6 and NaAlSi2O6–CaFe2+Si2O6 solid solutions. Phys Chem Miner 35:241–248
Tribaudino M, Bromiley G, Ohashi H, Nestola F (2009) Synthesis, TEM characterization and thermal behaviour of LiNiSi2O6 pyroxene. Phys Chem Miner 36:527–536
Ulrich A, Schranz W, Miletich R (2009) The nonlinear anomalous lattice elasticity associated with the high-pressure phase transition in spodumene: a high-precision static compression study. Phys Chem Miner 36:545–555
Yamanaka T, Hirano M, Takéuchi Y (1985) A high temperature transition in MgGeO3 from clinopyroxene (C2/c) type to orthopyroxene (Pbca) type. Am Mineral 70:365–374
Acknowledgments
We thank A. Di Giulio and A. Ceriani (Università di Pavia) for letting us use their heating stage and microscope. This work was supported by the Fonds zur Förderung der wissenschaftlichen Forschung, FWF, Vienna under grants number R33-N10 and P19762/N10. Finacial support to M. Alvaro and F. Nestola has been provided by Italian project MIUR: PRIN 2006047943 (Coordinator P. F. Zanazzi), Fernando Cámara was supported by funding by CNR-IGG through the project TAP01.004.002. The paper benefited from the critical reviews of Mario Tribaudino and an anonymous reviewer.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Redhammer, G.J., Cámara, F., Alvaro, M. et al. Thermal expansion and high-temperature P21/c–C2/c phase transition in clinopyroxene-type LiFeGe2O6 and comparison to NaFe(Si,Ge)2O6 . Phys Chem Minerals 37, 685–704 (2010). https://doi.org/10.1007/s00269-010-0368-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00269-010-0368-1