%0 Journal Article %1 McCord2001a %A McCord, T. B. %A Orlando, T. M. %A Teeter, G. %A Hansen, G. B. %A Sieger, M. T. %A Petrik, N. G. %A Keulen, L. Van %D 2001 %J Journal of Geophysical Research-Planets %K 0.65-2.5 DESORPTION; ENERGY GALILEAN ICY INFRARED MAPPING MU-M; NANO3 SATELLITES; SINGLE-CRYSTALS; SPECTRA; SPECTROMETER; SPECTROSCOPY; STIMULATED TEMPERATURE; %N E2 %P 3311--3319 %T Thermal and radiation stability of the hydrated salt minerals epsomite, mirabilite, and natron under Europa environmental conditions %V 106 %X We report studies on the thermal and radiolytic stability of the hydrated salt minerals epsomite (MgSO4. 7H(2)O), mirabilite (Na2SO4. 1OH(2)O), and natron (Na2CO3. 10H(2)O) under the low-temperature and ultrahigh vacuum conditions characteristic of the surface of the Galilean satellite Europa. We prepared samples, ran temperature-programmed dehydration (TPD) profiles and irradiated the samples with electrons. The TPD profiles are fit using Arrhenius-type first-order desorption kinetics, This analysis yields activation energies of 0.90 +/- 0.10, 0.70 +/- 0.07, and 0.45 +/- 0.05 eV for removal of the hydration water for epsomite, natron, and mirabilite, respectively. A simple extrapolation indicates that at Europa surface temperatures (less than or equal to 130 K), epsomite should remain hydrated over geologic timescales (similar to 10(11)-10(14) years), whereas natron and mirabilite may dehydrate appreciably in approximately 10(8) and 10(3) years, respectively. A small amount of SO2 was detected during and after 100 eV electron-beam irradiation of dehydrated epsomite and mirabilite samples, whereas products such as O-2 remained below detection limits. The upper limit for the 100 eV electron-induced damage cross section of mirabilite and epsomite is similar to 10(-19) cm(2). The overall radiolytic stability of these minerals is partially due to (1) the multiply charged nature of the sulfate anion, (2) the low probability of reversing the attractive Madelung (mostly the attractive electrostatic) potential via Auger decay, and (3) solid-state caging effects, Our laboratory results on the thermal and radiolytic stabilities of these salt minerals indicate that hydrated magnesium sulfate and perhaps other salts could exist for geologic timescales on the surface of Europa.

@article{McCord2001a, abstract = {We report studies on the thermal and radiolytic stability of the hydrated salt minerals epsomite (MgSO4. 7H(2)O), mirabilite (Na2SO4. 1OH(2)O), and natron (Na2CO3. 10H(2)O) under the low-temperature and ultrahigh vacuum conditions characteristic of the surface of the Galilean satellite Europa. We prepared samples, ran temperature-programmed dehydration (TPD) profiles and irradiated the samples with electrons. The TPD profiles are fit using Arrhenius-type first-order desorption kinetics, This analysis yields activation energies of 0.90 +/- 0.10, 0.70 +/- 0.07, and 0.45 +/- 0.05 eV for removal of the hydration water for epsomite, natron, and mirabilite, respectively. A simple extrapolation indicates that at Europa surface temperatures (less than or equal to 130 K), epsomite should remain hydrated over geologic timescales (similar to 10(11)-10(14) years), whereas natron and mirabilite may dehydrate appreciably in approximately 10(8) and 10(3) years, respectively. A small amount of SO2 was detected during and after 100 eV electron-beam irradiation of dehydrated epsomite and mirabilite samples, whereas products such as O-2 remained below detection limits. The upper limit for the 100 eV electron-induced damage cross section of mirabilite and epsomite is similar to 10(-19) cm(2). The overall radiolytic stability of these minerals is partially due to (1) the multiply charged nature of the sulfate anion, (2) the low probability of reversing the attractive Madelung (mostly the attractive electrostatic) potential via Auger decay, and (3) solid-state caging effects, Our laboratory results on the thermal and radiolytic stabilities of these salt minerals indicate that hydrated magnesium sulfate and perhaps other salts could exist for geologic timescales on the surface of Europa.}, added-at = {2009-11-03T20:21:25.000+0100}, author = {McCord, T. B. and Orlando, T. M. and Teeter, G. and Hansen, G. B. and Sieger, M. T. and Petrik, N. G. and Keulen, L. Van}, biburl = {https://www.bibsonomy.org/bibtex/2965e529316894e97440790a8cc9558c0/svance}, citedreferences = {CALABRESE A, 1975, J ELECTRON SPECTROSC, V6, P1 ; CALVIN WM, 1995, J GEOPHYS RES-PLANET, V100, P19041 ; CARLSON RW, 1992, SPACE SCI REV, V60, P457 ; CARLSON RW, 1999, Science, V286, P97 ; CLARK RN, 1980, Icarus, V41, P323 ; CLARK RN, 1980, Icarus, V44, P388 ; CLARK RN, 1981, J GEOPHYS RES, V86, P3087 ; COOPER JF, 2000, IN PRESS Icarus ; CROWLEY JK, 1991, J GEOPHYS RES-SOL EA, V96, P16231 ; CUNNINGHAM J, 1968, RADICAL IONS, P475 ; DALTON JB, 1998, B AM ASTRON SOC, V30, P1081 ; DALTON JB, 1998, EOS T AGU S, V79, F541 ; FANALE FP, 1977, PLANETARY SATELLITES, P379 ; FANALE FP, 1998, LUNAR PLANET SCI, V29 ; Greeley R, 1998, Icarus, V135, P4 ; Greenberg R, 1999, Icarus, V141, P263 ; HOPPA G, 1999, Icarus, V141, P287 ; HUANG SR, 1966, ASTM SPEC TECH PUBL, V40, P121 ; HUDSON JB, 1992, SURFACE SCI INTRO ; IP WH, 1998, GEOPHYS RES LETT, V25, P829 ; JOHNSON RE, 2000, Icarus, V143, P429 ; KARGEL JS, 1991, Icarus, V94, P368 ; KARGEL JS, 1999, LUNAR PLANET SCI, V30 ; KARGEL JS, 2000, Icarus, V148, P226 ; KNOTEK ML, 1978, PHYS REV LETT, V40, P964 ; KNUTSEN K, 1996, SURF SCI, V348, P143 ; KNUTSEN K, 1997, PHYS REV B, V55, P13246 ; KNUTSEN K, 1998, APPL SURF SCI, V127, P1 ; MCCORD TB, 1998, Science, V280, P1242 ; MCCORD TB, 1999, B AM ASTRON SOC, V31, P1171 ; MCCORD TB, 1999, EOS T AM GEOPHYS UN, V80, F599 ; MCCORD TB, 1999, J GEOPHYS RES, V104, P11824 ; MCCORD TB, 2000, LUNAR PLANET SCI, V31 ; NOVAK A, 1974, STRUCT BOND, V18, P177 ; PAPPALARDO RT, 1999, J GEOPHYS RES-PLANET, V104, P24015 ; PETRENKO VF, 1999, PHYSICS ICE ; PETRIK NG, 2000, J PHYS CHEM B, V104, P1563 ; SASAKI T, 1978, J CHEM PHYS, V68, P2718 ; SIEGER MT, 1998, Nature, V394, P554 ; TRETYAKOVA TV, 1980, RUSS J PHYS CHEM, V54, P2629 ; VANKEULEN L, 2000, LUNAR PLANET SCI, V31 ; ZOLOTOV MY, 1999, EOS T AGU S, V80, F604 ; ZOLOTOV MY, 2000, LUNAR PLANET SCI, V31}, interhash = {5b5c32ea87e5e0951c3b1a84c9fe538b}, intrahash = {965e529316894e97440790a8cc9558c0}, journal = {Journal of Geophysical Research-Planets}, keywords = {0.65-2.5 DESORPTION; ENERGY GALILEAN ICY INFRARED MAPPING MU-M; NANO3 SATELLITES; SINGLE-CRYSTALS; SPECTRA; SPECTROMETER; SPECTROSCOPY; STIMULATED TEMPERATURE;}, number = {E2}, owner = {svance}, pages = {3311--3319}, timestamp = {2009-11-03T20:22:01.000+0100}, title = {Thermal and radiation stability of the hydrated salt minerals epsomite, mirabilite, and natron under Europa environmental conditions}, volume = 106, year = 2001 }