TY - JOUR

T1 - Crystal Structure of Hydrotalcite Group Mineral—Desautelsite, Mg6MnIII2(OH)16(CO3)·4H2O, and Relationship between Cation Size and In-Plane Unit Cell Parameter

AU - Zhitova, Elena S.

AU - Sheveleva, Rezeda M.

AU - Kasatkin, Anatoly V.

AU - Zolotarev, Andrey A.

AU - Bocharov, Vladimir N.

AU - Kupchinenko, Anastasia N.

AU - Belakovsky, Dmitry I.

N1 - Zhitova, E.S.; Sheveleva, R.M.; Kasatkin, A.V.; Zolotarev, A.A.; Bocharov, V.N.; Kupchinenko, A.N.; Belakovsky, D.I. Crystal Structure of Hydrotalcite Group Mineral—Desautelsite, Mg6MnIII2(OH)16(CO3)·4H2O, and Relationship between Cation Size and In-Plane Unit Cell Parameter. Symmetry 2023, 15, 1029. https://doi.org/10.3390/sym15051029

PY - 2023/5/5

Y1 - 2023/5/5

N2 - The crystal structure of a naturally occurring layered double hydroxide mineral—desautelsite from San Benito County, California, USA—was refined using single-crystal X-ray diffraction data in the space group R-3m, a = 3.1238(2) Å, c = 23.528(3) Å, V = 198.83(4) Å3, and Z = 3/8. The Mg and Mn cations are disordered occurring in one M site with occupancy Mg0.77Mn0.23. According to the electron microprobe analysis supported by Raman spectroscopy, the empirical formula is Mg6.20(MnIII1.78Al0.01FeIII0.01)Σ1.80(OH)16(CO3)0.90·5.35H2O that shows higher content of interlayer (H2O) molecules in comparison to the ideal formula that also agrees with the structure refinement. The Raman spectroscopy of two samples indicated O–H vibrations (3650/3640 cm−1, ~3500 sh cm−1), symmetric C–O (1055/1057 cm−1), Mg–O–Mg (533/533 cm−1) and Mn–O–Mn (439/438 cm−1) stretching vibrations and lattice vibrations (284/287 cm−1). Summing up our data and that of the current literature, we show a correlation (R2 = 0.91) between the averaged effective ionic radius (x) and a unit cell parameter (y) of hydrotalcite group minerals, y=1.9871x+1.4455. Desautelsite follows this correlation, being the species with one of the largest a unit cell parameters among the group. The correlation can be applied for control of cation intercalation during synthesis.

AB - The crystal structure of a naturally occurring layered double hydroxide mineral—desautelsite from San Benito County, California, USA—was refined using single-crystal X-ray diffraction data in the space group R-3m, a = 3.1238(2) Å, c = 23.528(3) Å, V = 198.83(4) Å3, and Z = 3/8. The Mg and Mn cations are disordered occurring in one M site with occupancy Mg0.77Mn0.23. According to the electron microprobe analysis supported by Raman spectroscopy, the empirical formula is Mg6.20(MnIII1.78Al0.01FeIII0.01)Σ1.80(OH)16(CO3)0.90·5.35H2O that shows higher content of interlayer (H2O) molecules in comparison to the ideal formula that also agrees with the structure refinement. The Raman spectroscopy of two samples indicated O–H vibrations (3650/3640 cm−1, ~3500 sh cm−1), symmetric C–O (1055/1057 cm−1), Mg–O–Mg (533/533 cm−1) and Mn–O–Mn (439/438 cm−1) stretching vibrations and lattice vibrations (284/287 cm−1). Summing up our data and that of the current literature, we show a correlation (R2 = 0.91) between the averaged effective ionic radius (x) and a unit cell parameter (y) of hydrotalcite group minerals, y=1.9871x+1.4455. Desautelsite follows this correlation, being the species with one of the largest a unit cell parameters among the group. The correlation can be applied for control of cation intercalation during synthesis.

KW - desautelsite

KW - layered double hydroxide (LDH)

KW - structure

KW - mineral

KW - Raman

KW - chemical composition

KW - cation

KW - RADII

KW - radius

KW - size

KW - correlation

KW - radii

UR - https://www.mendeley.com/catalogue/77f36c49-2729-3862-8971-40069e3476c5/

U2 - 10.3390/sym15051029

DO - 10.3390/sym15051029

M3 - Article

VL - 15

SP - 1029

JO - Symmetry

JF - Symmetry

SN - 2073-8994

IS - 5

ER -