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A hydroxyl-dominant analogue of gadolinite-(Y) (OH-Gad) has been discovered in the Heftetjern granitic pegmatite, southern Norway, in association with late-stage rare-earth-element containing minerals. The empirical formula, based on ten O atoms per formula unit, is (Y1.285Ca0.55Ce0.07La0.04Nd0.01)Σ1.955(Fe2+0.570.43)Be2.02Si1.995O8.48(OH)1.52. The mineral is monoclinic, space group P21/c, a = 4.7514 (10), b = 7.5719 (16), c = 9.9414 (2) Å, β = 90.015 (4)°, V = 357.663 (3) Å3 and Z = 2. The density calculated using the empirical formula is 3.903 g cm−3. The crystal structure was refined to R = 0.0217 for 776 reflections with I > 2σ(I). OH-Gad is isostructural with gadolinite-(Y) and it is characterized by the predominance of OH over O2− at the anionic Ø-site. The refined crystal-chemical formula is: A(Y1.25Ca0.55Ce0.2)X(Fe2+0.570.43)ZBe2TSi2O8Ø[(OH)0.86O0.59(OH)*0.55] (Z = 2). The possible orientation and local environment of the hydroxyl group were suggested based on bond-valence sum calculations and geometrical analysis of the crystal structure. The infrared spectrum confirms disordering of H atoms. OH-Gad seems to be a potentially new mineral, the first simultaneously hydroxyl- and iron-dominant member of the gadolinite subgroup. It is an OH-analogue of gadolinite-(Y) and an Fe2+-analogue of hingganite-(Y).

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S2052520617006588/bp5096sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S2052520617006588/bp5096Isup2.hkl
Contains datablock I

pdf

Portable Document Format (PDF) file https://doi.org/10.1107/S2052520617006588/bp5096sup3.pdf
Tables S1 and S2

CCDC reference: 1547407

Computing details top

(I) top
Crystal data top
Be2Ca0.55Ce0.2Fe0.57O10Si2Y1.25F(000) = 404
Mr = 427.2Dx = 3.967 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ycbCell parameters from 5335 reflections
a = 4.7514 (10) Åθ = 3.4–32.6°
b = 7.5719 (16) ŵ = 13.28 mm1
c = 9.9414 (2) ÅT = 120 K
β = 90.015 (4)°Anhedral grain
V = 357.66 Å30.16 × 0.15 × 0.12 mm
Z = 2
Data collection top
Bruker Smart Apex 2
diffractometer
Rint = 0.04
Radiation source: X-ray tubeθmax = 32.6°, θmin = 3.4°
5335 measured reflectionsh = 66
841 independent reflectionsk = 1010
776 reflections with I > 2σ(I)l = 1414
Refinement top
Refinement on F38 constraints
R[F2 > 2σ(F2)] = 0.022Weighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.000289F2)
wR(F2) = 0.028(Δ/σ)max = 0.043
S = 0.98Δρmax = 0.49 e Å3
841 reflectionsΔρmin = 0.60 e Å3
90 parametersExtinction correction: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974)
0 restraintsExtinction coefficient: 230 (110)
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Y_a0.00066 (17)0.89222 (10)0.16974 (7)0.00668 (10)0.625
Fe_x00.500.0102 (3)0.57
Si_t0.51934 (16)1.22271 (10)0.07879 (7)0.0093 (2)
O10.2388 (5)0.9118 (3)0.0311 (2)0.0130 (6)
O50.2083 (5)1.0882 (3)0.3310 (2)0.0147 (6)
O20.3057 (5)1.1536 (3)0.1954 (2)0.0131 (5)
O30.3152 (5)0.8938 (2)0.3561 (2)0.0130 (6)
O40.3261 (4)0.7140 (3)0.0491 (2)0.0118 (5)
Be_z0.5446 (8)1.0866 (4)0.3356 (3)0.0068 (8)
Ca_a0.00066 (17)0.89222 (10)0.16974 (7)0.00668 (10)0.275
Ce_a0.00066 (17)0.89222 (10)0.16974 (7)0.00668 (10)0.1
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Y_a0.00517 (16)0.00833 (17)0.00656 (16)0.00034 (8)0.00062 (9)0.00083 (8)
Fe_x0.0072 (4)0.0152 (5)0.0082 (4)0.0003 (3)0.0002 (3)0.0023 (3)
Si_t0.0080 (4)0.0105 (3)0.0095 (4)0.0000 (3)0.0007 (3)0.0007 (2)
O10.0091 (10)0.0144 (10)0.0154 (10)0.0037 (7)0.0009 (8)0.0012 (7)
O50.0097 (10)0.0200 (10)0.0146 (10)0.0002 (8)0.0017 (8)0.0001 (8)
O20.0103 (10)0.0183 (10)0.0106 (9)0.0027 (8)0.0015 (7)0.0017 (8)
O30.0137 (10)0.0101 (9)0.0152 (10)0.0023 (7)0.0024 (8)0.0011 (7)
O40.0123 (10)0.0128 (9)0.0104 (9)0.0013 (7)0.0017 (8)0.0034 (7)
Be_z0.0060 (14)0.0070 (14)0.0074 (15)0.0019 (10)0.0010 (11)0.0006 (10)
Ca_a0.00517 (16)0.00833 (17)0.00656 (16)0.00034 (8)0.00062 (9)0.00083 (8)
Ce_a0.00517 (16)0.00833 (17)0.00656 (16)0.00034 (8)0.00062 (9)0.00083 (8)
Geometric parameters (Å, º) top
Y_a—Y_ai3.7489 (10)O1—Ce_ai2.322 (2)
Y_a—O12.300 (2)O5—Be_z1.599 (4)
Y_a—O1i2.322 (2)O5—Ca_a2.400 (2)
Y_a—O52.400 (2)O5—Ce_a2.400 (2)
Y_a—O32.381 (3)O5—Ce_avi2.504 (2)
Y_a—O42.381 (2)O2—Be_zvii1.645 (4)
Y_a—Ca_a0O2—Ce_a2.466 (2)
Y_a—Ca_ai3.7489 (10)O3—Be_zvii1.618 (4)
Y_a—Ce_a0O3—Ca_a2.381 (3)
Y_a—Ce_ai3.7489 (10)O3—Ce_a2.381 (3)
Fe_x—O5ii2.061 (2)O4—Be_zviii1.619 (4)
Fe_x—O5iii2.061 (2)O4—Ca_a2.381 (2)
Fe_x—Ca_aii3.3831 (7)O4—Ce_a2.381 (2)
Fe_x—Ca_aiii3.3831 (7)Be_z—Ca_aix3.091 (4)
Si_t—O1iv1.607 (2)Be_z—Ca_ax3.171 (4)
Si_t—O21.628 (2)Ca_a—Ca_aii4.1085 (10)
Si_t—O3v1.648 (2)Ca_a—Ca_avi4.1085 (10)
Si_t—O4i1.640 (2)Ca_a—Ca_ai3.7489 (10)
O1—Ca_a2.300 (2)Ca_a—Ce_a0
O1—Ca_ai2.322 (2)Ca_a—Ce_ai3.7489 (10)
O1—Ce_a2.300 (2)Ce_a—Ce_ai3.7489 (10)
Y_ai—Y_a—O136.01 (6)Y_ai—Ca_a—Be_zvii105.90 (7)
Y_ai—Y_a—O1i35.61 (6)Y_ai—Ca_a—Be_zviii107.55 (7)
Y_ai—Y_a—O5109.36 (6)Y_ai—Ca_a—Ca_aii138.66 (2)
Y_ai—Y_a—O3134.39 (6)Y_ai—Ca_a—Ca_avi87.05 (2)
Y_ai—Y_a—O478.01 (5)Y_ai—Ca_a—Ca_ai0.0 (5)
Y_ai—Y_a—Ca_a0Y_ai—Ca_a—Ce_a0
Y_ai—Y_a—Ca_ai0.0 (5)Y_ai—Ca_a—Ce_ai0.0 (5)
Y_ai—Y_a—Ce_a0Fe_xvi—Ca_a—O1145.84 (6)
Y_ai—Y_a—Ce_ai0.0 (5)Fe_xvi—Ca_a—O1i114.91 (6)
O1—Y_a—O1i71.61 (8)Fe_xvi—Ca_a—O537.07 (6)
O1—Y_a—O5138.04 (8)Fe_xvi—Ca_a—O340.89 (6)
O1—Y_a—O3111.51 (9)Fe_xvi—Ca_a—O4128.68 (6)
O1—Y_a—O485.41 (8)Fe_xvi—Ca_a—Be_zvii50.81 (7)
O1—Y_a—Ca_a0Fe_xvi—Ca_a—Be_zviii101.05 (6)
O1—Y_a—Ca_ai36.01 (6)Fe_xvi—Ca_a—Ca_aii81.104 (18)
O1—Y_a—Ce_a0Fe_xvi—Ca_a—Ca_avi53.186 (14)
O1—Y_a—Ce_ai36.01 (6)Fe_xvi—Ca_a—Ca_ai140.23 (2)
O1i—Y_a—O578.38 (8)Fe_xvi—Ca_a—Ce_a0
O1i—Y_a—O3140.00 (8)Fe_xvi—Ca_a—Ce_ai140.23 (2)
O1i—Y_a—O475.16 (8)O1—Ca_a—O1i71.61 (8)
O1i—Y_a—Ca_a0O1—Ca_a—O5138.04 (8)
O1i—Y_a—Ca_ai35.61 (6)O1—Ca_a—O3111.51 (9)
O1i—Y_a—Ce_a0O1—Ca_a—O485.41 (8)
O1i—Y_a—Ce_ai35.61 (6)O1—Ca_a—Be_zvii95.08 (9)
O5—Y_a—O374.73 (8)O1—Ca_a—Be_zviii111.64 (9)
O5—Y_a—O4114.66 (8)O1—Ca_a—Ca_aii113.42 (6)
O5—Y_a—Ca_a0O1—Ca_a—Ca_avi106.17 (6)
O5—Y_a—Ca_ai109.36 (6)O1—Ca_a—Ca_ai36.01 (6)
O5—Y_a—Ce_a0O1—Ca_a—Ce_a0
O5—Y_a—Ce_ai109.36 (6)O1—Ca_a—Ce_ai36.01 (6)
O3—Y_a—O4143.53 (8)O1i—Ca_a—O578.38 (8)
O3—Y_a—Ca_a0O1i—Ca_a—O3140.00 (8)
O3—Y_a—Ca_ai134.39 (6)O1i—Ca_a—O475.16 (8)
O3—Y_a—Ce_a0O1i—Ca_a—Be_zvii110.77 (9)
O3—Y_a—Ce_ai134.39 (6)O1i—Ca_a—Be_zviii96.98 (9)
O4—Y_a—Ca_a0O1i—Ca_a—Ca_aii144.92 (6)
O4—Y_a—Ca_ai78.01 (5)O1i—Ca_a—Ca_avi68.96 (6)
O4—Y_a—Ce_a0O1i—Ca_a—Ca_ai35.61 (6)
O4—Y_a—Ce_ai78.01 (5)O1i—Ca_a—Ce_a0
Ca_a—Y_a—Ca_ai0O1i—Ca_a—Ce_ai35.61 (6)
Ca_a—Y_a—Ce_a0O5—Ca_a—O374.73 (8)
Ca_a—Y_a—Ce_ai0O5—Ca_a—O4114.66 (8)
Ca_ai—Y_a—Ce_a0O5—Ca_a—Be_zvii68.80 (9)
Ca_ai—Y_a—Ce_ai0.0 (5)O5—Ca_a—Be_zviii100.36 (9)
Ce_a—Y_a—Ce_ai0O5—Ca_a—Ca_aii108.05 (6)
O5ii—Fe_x—O5iii180.0 (5)O5—Ca_a—Ca_avi33.90 (6)
O5ii—Fe_x—Ca_aii44.57 (6)O5—Ca_a—Ca_ai109.36 (6)
O5ii—Fe_x—Ca_aiii135.43 (6)O5—Ca_a—Ce_a0
O5iii—Fe_x—Ca_aii135.43 (6)O5—Ca_a—Ce_ai109.36 (6)
O5iii—Fe_x—Ca_aiii44.57 (6)O3—Ca_a—O4143.53 (8)
Ca_aii—Fe_x—Ca_aiii180.0 (5)O3—Ca_a—Be_zvii31.08 (8)
O1iv—Si_t—O2116.88 (12)O3—Ca_a—Be_zviii116.47 (8)
O1iv—Si_t—O3v105.84 (12)O3—Ca_a—Ca_aii72.74 (5)
O1iv—Si_t—O4i110.94 (12)O3—Ca_a—Ca_avi72.18 (5)
O2—Si_t—O3v105.71 (12)O3—Ca_a—Ca_ai134.39 (6)
O2—Si_t—O4i107.28 (12)O3—Ca_a—Ce_a0
O3v—Si_t—O4i109.97 (11)O3—Ca_a—Ce_ai134.39 (6)
Y_a—O1—Y_ai108.39 (9)O4—Ca_a—Be_zvii173.91 (9)
Y_a—O1—Si_tiv124.52 (12)O4—Ca_a—Be_zviii29.82 (8)
Y_a—O1—Ca_a0.0 (5)O4—Ca_a—Ca_aii70.87 (5)
Y_a—O1—Ca_ai108.39 (9)O4—Ca_a—Ca_avi135.80 (6)
Y_a—O1—Ce_a0.0 (5)O4—Ca_a—Ca_ai78.01 (5)
Y_a—O1—Ce_ai108.39 (9)O4—Ca_a—Ce_a0
Y_ai—O1—Si_tiv125.47 (13)O4—Ca_a—Ce_ai78.01 (5)
Y_ai—O1—Ca_a108.39 (9)Be_zvii—Ca_a—Be_zviii146.53 (9)
Y_ai—O1—Ca_ai0.0 (5)Be_zvii—Ca_a—Ca_aii103.46 (7)
Y_ai—O1—Ce_a108.39 (9)Be_zvii—Ca_a—Ca_avi49.84 (7)
Y_ai—O1—Ce_ai0.0 (5)Be_zvii—Ca_a—Ca_ai105.90 (7)
Si_tiv—O1—Ca_a124.52 (12)Be_zvii—Ca_a—Ce_a0
Si_tiv—O1—Ca_ai125.47 (13)Be_zvii—Ca_a—Ce_ai105.90 (7)
Si_tiv—O1—Ce_a124.52 (12)Be_zviii—Ca_a—Ca_aii48.16 (6)
Si_tiv—O1—Ce_ai125.47 (13)Be_zviii—Ca_a—Ca_avi132.69 (7)
Ca_a—O1—Ca_ai108.39 (9)Be_zviii—Ca_a—Ca_ai107.55 (7)
Ca_a—O1—Ce_a0.0 (5)Be_zviii—Ca_a—Ce_a0
Ca_a—O1—Ce_ai108.39 (9)Be_zviii—Ca_a—Ce_ai107.55 (7)
Ca_ai—O1—Ce_a108.39 (9)Ca_aii—Ca_a—Ca_avi134.29 (2)
Ca_ai—O1—Ce_ai0.0 (5)Ca_aii—Ca_a—Ca_ai138.66 (2)
Ce_a—O1—Ce_ai108.39 (9)Ca_aii—Ca_a—Ce_a0
Y_a—O5—Fe_xvi98.36 (9)Ca_aii—Ca_a—Ce_ai138.66 (2)
Y_a—O5—Be_z115.34 (17)Ca_avi—Ca_a—Ca_ai87.05 (2)
Y_a—O5—Ca_a0.0 (5)Ca_avi—Ca_a—Ce_a0
Y_a—O5—Ce_a0.0 (5)Ca_avi—Ca_a—Ce_ai87.05 (2)
Y_a—O5—Ce_avi113.80 (10)Ca_ai—Ca_a—Ce_a0
Fe_xvi—O5—Be_z117.01 (18)Ca_ai—Ca_a—Ce_ai0.0 (5)
Fe_xvi—O5—Ca_a98.36 (9)Ce_a—Ca_a—Ce_ai0
Fe_xvi—O5—Ce_a98.36 (9)Y_a—Ce_a—Y_ai0
Fe_xvi—O5—Ce_avi96.38 (9)Y_a—Ce_a—O10
Be_z—O5—Ca_a115.34 (17)Y_a—Ce_a—O1i0
Be_z—O5—Ce_a115.34 (17)Y_a—Ce_a—O50
Be_z—O5—Ce_avi113.63 (16)Y_a—Ce_a—O5ii0
Ca_a—O5—Ce_a0.0 (5)Y_a—Ce_a—O20
Ca_a—O5—Ce_avi113.80 (10)Y_a—Ce_a—O30
Ce_a—O5—Ce_avi113.80 (10)Y_a—Ce_a—O40
Si_t—O2—Be_zvii115.65 (19)Y_a—Ce_a—Ca_a0
Si_t—O2—Ce_a123.44 (12)Y_a—Ce_a—Ca_ai0
Be_zvii—O2—Ce_a95.43 (16)Y_a—Ce_a—Ce_ai0
Y_a—O3—Si_txi126.95 (11)Y_ai—Ce_a—O136.01 (6)
Y_a—O3—Be_zvii99.47 (16)Y_ai—Ce_a—O1i35.61 (6)
Y_a—O3—Ca_a0.0 (5)Y_ai—Ce_a—O5109.36 (6)
Y_a—O3—Ce_a0.0 (5)Y_ai—Ce_a—O5ii113.47 (6)
Si_txi—O3—Be_zvii124.3 (2)Y_ai—Ce_a—O275.21 (5)
Si_txi—O3—Ca_a126.95 (11)Y_ai—Ce_a—O3134.39 (6)
Si_txi—O3—Ce_a126.95 (11)Y_ai—Ce_a—O478.01 (5)
Be_zvii—O3—Ca_a99.47 (16)Y_ai—Ce_a—Ca_a0
Be_zvii—O3—Ce_a99.47 (16)Y_ai—Ce_a—Ca_ai0.0 (5)
Ca_a—O3—Ce_a0.0 (5)Y_ai—Ce_a—Ce_ai0.0 (5)
Y_a—O4—Si_ti126.14 (11)O1—Ce_a—O1i71.61 (8)
Y_a—O4—Be_zviii103.19 (16)O1—Ce_a—O5138.04 (8)
Y_a—O4—Ca_a0.0 (5)O1—Ce_a—O5ii82.13 (8)
Y_a—O4—Ce_a0.0 (5)O1—Ce_a—O275.46 (8)
Si_ti—O4—Be_zviii120.71 (18)O1—Ce_a—O3111.51 (9)
Si_ti—O4—Ca_a126.14 (11)O1—Ce_a—O485.41 (8)
Si_ti—O4—Ce_a126.14 (11)O1—Ce_a—Ca_a0
Be_zviii—O4—Ca_a103.19 (16)O1—Ce_a—Ca_ai36.01 (6)
Be_zviii—O4—Ce_a103.19 (16)O1—Ce_a—Ce_ai36.01 (6)
Ca_a—O4—Ce_a0.0 (5)O1i—Ce_a—O578.38 (8)
O5—Be_z—O2ix113.9 (2)O1i—Ce_a—O5ii141.11 (8)
O5—Be_z—O3ix115.0 (2)O1i—Ce_a—O280.60 (8)
O5—Be_z—O4x113.3 (2)O1i—Ce_a—O3140.00 (8)
O5—Be_z—Ca_aix133.40 (19)O1i—Ce_a—O475.16 (8)
O5—Be_z—Ca_ax132.62 (18)O1i—Ce_a—Ca_a0
O2ix—Be_z—O3ix102.0 (2)O1i—Ce_a—Ca_ai35.61 (6)
O2ix—Be_z—O4x104.6 (2)O1i—Ce_a—Ce_ai35.61 (6)
O2ix—Be_z—Ca_aix52.59 (13)O5—Ce_a—O5ii137.17 (8)
O2ix—Be_z—Ca_ax57.68 (13)O5—Ce_a—O271.20 (8)
O3ix—Be_z—O4x107.0 (2)O5—Ce_a—O374.73 (8)
O3ix—Be_z—Ca_aix49.45 (13)O5—Ce_a—O4114.66 (8)
O3ix—Be_z—Ca_ax112.31 (19)O5—Ce_a—Ca_a0
O4x—Be_z—Ca_aix113.34 (19)O5—Ce_a—Ca_ai109.36 (6)
O4x—Be_z—Ca_ax46.99 (12)O5—Ce_a—Ce_ai109.36 (6)
Ca_aix—Be_z—Ca_ax82.01 (9)O5ii—Ce_a—O2120.42 (8)
Y_a—Ca_a—Y_ai0O5ii—Ce_a—O376.09 (7)
Y_a—Ca_a—Fe_xvi0O5ii—Ce_a—O474.60 (8)
Y_a—Ca_a—O10O5ii—Ce_a—Ca_a0
Y_a—Ca_a—O1i0O5ii—Ce_a—Ca_ai113.47 (6)
Y_a—Ca_a—O50O5ii—Ce_a—Ce_ai113.47 (6)
Y_a—Ca_a—O30O2—Ce_a—O363.03 (7)
Y_a—Ca_a—O40O2—Ce_a—O4152.88 (8)
Y_a—Ca_a—Be_zvii0O2—Ce_a—Ca_a0
Y_a—Ca_a—Be_zviii0O2—Ce_a—Ca_ai75.21 (5)
Y_a—Ca_a—Ca_aii0O2—Ce_a—Ce_ai75.21 (5)
Y_a—Ca_a—Ca_avi0O3—Ce_a—O4143.53 (8)
Y_a—Ca_a—Ca_ai0O3—Ce_a—Ca_a0
Y_a—Ca_a—Ce_a0O3—Ce_a—Ca_ai134.39 (6)
Y_a—Ca_a—Ce_ai0O3—Ce_a—Ce_ai134.39 (6)
Y_ai—Ca_a—Fe_xvi140.23 (2)O4—Ce_a—Ca_a0
Y_ai—Ca_a—O136.01 (6)O4—Ce_a—Ca_ai78.01 (5)
Y_ai—Ca_a—O1i35.61 (6)O4—Ce_a—Ce_ai78.01 (5)
Y_ai—Ca_a—O5109.36 (6)Ca_a—Ce_a—Ca_ai0
Y_ai—Ca_a—O3134.39 (6)Ca_a—Ce_a—Ce_ai0
Y_ai—Ca_a—O478.01 (5)Ca_ai—Ce_a—Ce_ai0.0 (5)
Symmetry codes: (i) x, y+2, z; (ii) x, y1/2, z+1/2; (iii) x, y+3/2, z1/2; (iv) x+1, y+2, z; (v) x+1, y+1/2, z+1/2; (vi) x, y+1/2, z+1/2; (vii) x+1, y, z; (viii) x1, y1/2, z+1/2; (ix) x1, y, z; (x) x1, y+1/2, z+1/2; (xi) x+1, y1/2, z+1/2.
 

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