Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536809007211/mg2062sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536809007211/mg2062Isup2.hkl |
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean (Ge-Sc) = 0.003 Å
- Disorder in main residue
- R factor = 0.031
- wR factor = 0.066
- Data-to-parameter ratio = 19.6
checkCIF/PLATON results
No syntax errors found
Alert level C Value of measurement temperature given = 298.000 Value of melting point given = 0.000 PLAT301_ALERT_3_C Main Residue Disorder ......................... 20.00 Perc. PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings Differ .... ? PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ? PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............ 0.50 Ratio PLAT068_ALERT_1_C Reported F000 Differs from Calcd (or Missing)... ? PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent ..... ?
Alert level G PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE1 -GD2 2.664 1.555 2.664 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE1 -GD2 6.657 1.555 6.657 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. GD1 -GE1 -SC1 6.556 1.555 6.556 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE2 -GD2 8.665 1.555 8.665 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE2 -GD2 2.564 1.555 2.564 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE2 -GD2 3.656 1.555 3.656 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. GD2 -GE2 -SC2 5.666 1.555 5.666 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE3 -GD2 3.657 1.555 3.657 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. SC2 -GE3 -GD2 5.667 1.555 5.667 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. GD1 -GE3 -SC1 8.766 1.555 8.766 PLAT779_ALERT_4_G Suspect or Irrelevant (Bond) Angle in CIF ...... 0.00 Deg. GD1 -GE3 -SC1 2.665 1.555 2.665
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 6 ALERT level C = Check and explain 11 ALERT level G = General alerts; check 5 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 11 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
Gd2Sc3Ge4 was prepared by arc-melting pieces of the constituent elements (Gd, 99.99 wt. %, Materials Preparation Center, Ames Laboratory; Sc, 99.99 wt. %, Materials Preparation Center, Ames Laboratory; Ge, 99.9999 wt. %, Alfa Aesar) in an argon atmosphere on a water-cooled copper hearth. The ingot had a total weight of ca. 0.8 g and was remelted six times with the button being turned over after each melting to ensure homogeneity. Weight losses during melting were less than 0.1 wt. %.
A disordered model works best compared to an ordered model and this has been confirmed by a Hamilton's significance test on the crystallographic R factor. We formulated four hypotheses to be tested: (A) M1 site is all Gd, M2 site is all Sc; (B) M1 site is all Gd, M2 site is mixed with Gd and Sc; (C) M1 site is mixed with Gd and Sc, M1 site is all Sc; and (D) both M1 and M2 sites are mixed with Gd and Sc. The number of parameters refined in the four cases were mA = 47, mB = 48, mC = 48, and mD = 49. There were 958 reflections. The R factors achieved were RA = 0.0333, RB = 0.0318, RC = 0.0326, and RD = 0.0313. We could reject hypotheses (A), (B), and (C) at the 0.5% level of significance corresponding to hypothesis (D).
Data collection: SMART (Bruker, 2002); cell refinement: SMART (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Fig. 1. View of Gd2Sc3Ge4 along [001], with displacement ellipsoids drawn at the 99 % probability level. |
Gd2Sc3Ge4 | F(000) = 1276 |
Mr = 739.74 | Dx = 6.419 Mg m−3 |
Orthorhombic, Pnma | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2n | Cell parameters from 6182 reflections |
a = 7.2445 (13) Å | θ = 3.1–27.8° |
b = 14.101 (3) Å | µ = 34.91 mm−1 |
c = 7.4930 (14) Å | T = 298 K |
V = 765.4 (2) Å3 | Plate, grey |
Z = 4 | 0.06 × 0.05 × 0.01 mm |
Bruker SMART CCD area-detector diffractometer | 958 independent reflections |
Radiation source: fine-focus sealed tube | 816 reflections with I > 2s(I) |
Graphite monochromator | Rint = 0.070 |
ϕ and ω scans | θmax = 28.2°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | h = −9→9 |
Tmin = 0.127, Tmax = 0.705 | k = −17→18 |
6182 measured reflections | l = −9→9 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.031 | w = 1/[σ2(Fo2) + (0.0171P)2 + 3.8343P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.066 | (Δ/σ)max = 0.001 |
S = 1.05 | Δρmax = 2.20 e Å−3 |
958 reflections | Δρmin = −1.44 e Å−3 |
49 parameters | Extinction correction: SHELXL97 (Bruker, 2002), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.00245 (16) |
Gd2Sc3Ge4 | V = 765.4 (2) Å3 |
Mr = 739.74 | Z = 4 |
Orthorhombic, Pnma | Mo Kα radiation |
a = 7.2445 (13) Å | µ = 34.91 mm−1 |
b = 14.101 (3) Å | T = 298 K |
c = 7.4930 (14) Å | 0.06 × 0.05 × 0.01 mm |
Bruker SMART CCD area-detector diffractometer | 958 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 816 reflections with I > 2s(I) |
Tmin = 0.127, Tmax = 0.705 | Rint = 0.070 |
6182 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 49 parameters |
wR(F2) = 0.066 | 0 restraints |
S = 1.05 | Δρmax = 2.20 e Å−3 |
958 reflections | Δρmin = −1.44 e Å−3 |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Gd1 | 0.99788 (5) | 0.40395 (3) | 0.17641 (5) | 0.00746 (16) | 0.967 (4) |
Sc1 | 0.99788 (5) | 0.40395 (3) | 0.17641 (5) | 0.00746 (16) | 0.033 (4) |
Gd2 | 0.6602 (2) | 0.37594 (9) | 0.83229 (17) | 0.0081 (5) | 0.031 (3) |
Sc2 | 0.6602 (2) | 0.37594 (9) | 0.83229 (17) | 0.0081 (5) | 0.969 (3) |
Sc3 | 0.1761 (3) | 0.7500 | 0.5005 (3) | 0.0072 (4) | |
Ge1 | 0.82216 (12) | 0.45888 (6) | 0.54068 (11) | 0.0091 (2) | |
Ge2 | 0.03997 (16) | 0.7500 | 0.12561 (16) | 0.0081 (3) | |
Ge3 | 0.30680 (16) | 0.7500 | 0.86322 (15) | 0.0081 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Gd1 | 0.0064 (2) | 0.0085 (2) | 0.0074 (2) | 0.00025 (14) | 0.00024 (15) | 0.00013 (15) |
Sc1 | 0.0064 (2) | 0.0085 (2) | 0.0074 (2) | 0.00025 (14) | 0.00024 (15) | 0.00013 (15) |
Gd2 | 0.0095 (8) | 0.0083 (7) | 0.0065 (8) | 0.0000 (5) | 0.0006 (5) | 0.0001 (5) |
Sc2 | 0.0095 (8) | 0.0083 (7) | 0.0065 (8) | 0.0000 (5) | 0.0006 (5) | 0.0001 (5) |
Sc3 | 0.0067 (10) | 0.0079 (10) | 0.0072 (10) | 0.000 | 0.0000 (8) | 0.000 |
Ge1 | 0.0113 (5) | 0.0086 (4) | 0.0073 (4) | 0.0011 (3) | −0.0009 (3) | 0.0008 (3) |
Ge2 | 0.0068 (6) | 0.0098 (6) | 0.0077 (6) | 0.000 | 0.0012 (5) | 0.000 |
Ge3 | 0.0085 (6) | 0.0082 (6) | 0.0077 (6) | 0.000 | −0.0008 (5) | 0.000 |
Gd1—Ge3i | 2.9452 (9) | Sc3—Gd2xiv | 3.268 (2) |
Gd1—Ge1ii | 2.9605 (10) | Sc3—Sc2xii | 3.283 (2) |
Gd1—Ge1 | 3.1097 (10) | Sc3—Gd2iii | 3.283 (2) |
Gd1—Ge3iii | 3.1101 (10) | Ge1—Sc2i | 2.8070 (16) |
Gd1—Ge2iv | 3.1478 (10) | Ge1—Gd2i | 2.8070 (16) |
Gd1—Ge1v | 3.1519 (10) | Ge1—Sc2xv | 2.8759 (17) |
Gd1—Ge1i | 3.1861 (10) | Ge1—Gd2xv | 2.8759 (17) |
Gd1—Sc3i | 3.4681 (17) | Ge1—Ge1v | 2.8907 (17) |
Gd1—Sc3iii | 3.4877 (17) | Ge1—Gd1xvi | 2.9605 (10) |
Gd1—Sc2i | 3.5083 (15) | Ge1—Sc1xvi | 2.9605 (10) |
Gd1—Gd2i | 3.5083 (15) | Ge1—Sc3iii | 2.9614 (10) |
Gd1—Gd2vi | 3.5762 (15) | Ge2—Ge3vi | 2.7572 (17) |
Gd2—Ge1 | 2.7421 (15) | Ge2—Sc2xiv | 2.7668 (16) |
Gd2—Ge2vii | 2.7668 (16) | Ge2—Gd2xiv | 2.7668 (16) |
Gd2—Ge1viii | 2.8070 (16) | Ge2—Sc2xiii | 2.7668 (16) |
Gd2—Ge2iii | 2.8234 (17) | Ge2—Gd2xiii | 2.7668 (16) |
Gd2—Ge1ix | 2.8759 (17) | Ge2—Sc3xvi | 2.800 (2) |
Gd2—Ge3x | 2.9010 (16) | Ge2—Sc2xii | 2.8234 (17) |
Gd2—Sc3vii | 3.268 (2) | Ge2—Gd2xii | 2.8234 (17) |
Gd2—Sc3iii | 3.283 (2) | Ge2—Gd2iii | 2.8234 (17) |
Gd2—Gd1viii | 3.5083 (15) | Ge2—Sc2iii | 2.8234 (17) |
Gd2—Sc1viii | 3.5083 (15) | Ge2—Sc1iv | 3.1478 (10) |
Gd2—Sc2xi | 3.552 (3) | Ge3—Ge2xvii | 2.7572 (17) |
Gd2—Gd2xi | 3.552 (3) | Ge3—Sc3xv | 2.864 (2) |
Sc3—Ge2ii | 2.800 (2) | Ge3—Sc2xviii | 2.9010 (16) |
Sc3—Ge3ix | 2.864 (2) | Ge3—Gd2xviii | 2.9010 (16) |
Sc3—Ge3 | 2.878 (2) | Ge3—Sc2x | 2.9010 (16) |
Sc3—Ge1xii | 2.9614 (10) | Ge3—Gd2x | 2.9010 (16) |
Sc3—Ge1iii | 2.9614 (10) | Ge3—Gd1xix | 2.9452 (9) |
Sc3—Ge2 | 2.977 (2) | Ge3—Sc1xix | 2.9452 (9) |
Sc3—Sc2xiii | 3.268 (2) | Ge3—Gd1viii | 2.9452 (9) |
Sc3—Gd2xiii | 3.268 (2) | Ge3—Sc1viii | 2.9452 (9) |
Sc3—Sc2xiv | 3.268 (2) | Ge3—Gd1iii | 3.1101 (10) |
Ge3i—Gd1—Ge1ii | 94.17 (3) | Ge3ix—Sc3—Gd2iii | 127.47 (6) |
Ge3i—Gd1—Ge1 | 87.88 (3) | Ge3—Sc3—Gd2iii | 126.76 (6) |
Ge1ii—Gd1—Ge1 | 137.90 (3) | Ge1xii—Sc3—Gd2iii | 117.23 (7) |
Ge3i—Gd1—Ge3iii | 82.64 (2) | Ge1iii—Sc3—Gd2iii | 51.79 (3) |
Ge1ii—Gd1—Ge3iii | 133.89 (3) | Ge2—Sc3—Gd2iii | 53.35 (4) |
Ge1—Gd1—Ge3iii | 88.12 (3) | Sc2xiii—Sc3—Gd2iii | 71.49 (4) |
Ge3i—Gd1—Ge2iv | 82.83 (3) | Gd2xiii—Sc3—Gd2iii | 71.49 (4) |
Ge1ii—Gd1—Ge2iv | 81.64 (3) | Sc2xiv—Sc3—Gd2iii | 105.69 (6) |
Ge1—Gd1—Ge2iv | 140.09 (3) | Gd2xiv—Sc3—Gd2iii | 105.69 (6) |
Ge3iii—Gd1—Ge2iv | 52.28 (3) | Sc2xii—Sc3—Gd2iii | 65.50 (6) |
Ge3i—Gd1—Ge1v | 86.21 (3) | Gd2—Ge1—Sc2i | 144.75 (4) |
Ge1ii—Gd1—Ge1v | 83.153 (17) | Gd2—Ge1—Gd2i | 144.75 (4) |
Ge1—Gd1—Ge1v | 54.98 (3) | Sc2i—Ge1—Gd2i | 0.00 (5) |
Ge3iii—Gd1—Ge1v | 141.82 (3) | Gd2—Ge1—Sc2xv | 85.83 (4) |
Ge2iv—Gd1—Ge1v | 160.52 (3) | Sc2i—Ge1—Sc2xv | 118.86 (4) |
Ge3i—Gd1—Ge1i | 161.59 (3) | Gd2i—Ge1—Sc2xv | 118.86 (4) |
Ge1ii—Gd1—Ge1i | 104.08 (3) | Gd2—Ge1—Gd2xv | 85.83 (4) |
Ge1—Gd1—Ge1i | 80.275 (17) | Sc2i—Ge1—Gd2xv | 118.86 (4) |
Ge3iii—Gd1—Ge1i | 82.92 (3) | Gd2i—Ge1—Gd2xv | 118.86 (4) |
Ge2iv—Gd1—Ge1i | 97.23 (3) | Sc2xv—Ge1—Gd2xv | 0.00 (7) |
Ge1v—Gd1—Ge1i | 98.23 (3) | Gd2—Ge1—Ge1v | 136.10 (5) |
Ge3i—Gd1—Sc3i | 52.57 (4) | Sc2i—Ge1—Ge1v | 60.61 (4) |
Ge1ii—Gd1—Sc3i | 54.16 (3) | Gd2i—Ge1—Ge1v | 60.61 (4) |
Ge1—Gd1—Sc3i | 140.20 (4) | Sc2xv—Ge1—Ge1v | 58.26 (4) |
Ge3iii—Gd1—Sc3i | 90.58 (3) | Gd2xv—Ge1—Ge1v | 58.26 (4) |
Ge2iv—Gd1—Sc3i | 49.79 (4) | Gd2—Ge1—Gd1xvi | 89.24 (4) |
Ge1v—Gd1—Sc3i | 110.99 (4) | Sc2i—Ge1—Gd1xvi | 86.99 (4) |
Ge1i—Gd1—Sc3i | 138.95 (4) | Gd2i—Ge1—Gd1xvi | 86.99 (4) |
Ge3i—Gd1—Sc3iii | 52.04 (4) | Sc2xv—Ge1—Gd1xvi | 138.69 (4) |
Ge1ii—Gd1—Sc3iii | 146.21 (4) | Gd2xv—Ge1—Gd1xvi | 138.69 (4) |
Ge1—Gd1—Sc3iii | 52.97 (3) | Ge1v—Ge1—Gd1xvi | 134.14 (5) |
Ge3iii—Gd1—Sc3iii | 51.34 (4) | Gd2—Ge1—Sc1xvi | 89.24 (4) |
Ge2iv—Gd1—Sc3iii | 92.20 (3) | Sc2i—Ge1—Sc1xvi | 86.99 (4) |
Ge1v—Gd1—Sc3iii | 93.70 (4) | Gd2i—Ge1—Sc1xvi | 86.99 (4) |
Ge1i—Gd1—Sc3iii | 109.66 (4) | Sc2xv—Ge1—Sc1xvi | 138.69 (4) |
Sc3i—Gd1—Sc3iii | 96.92 (4) | Gd2xv—Ge1—Sc1xvi | 138.69 (4) |
Ge3i—Gd1—Sc2i | 130.59 (3) | Ge1v—Ge1—Sc1xvi | 134.14 (5) |
Ge1ii—Gd1—Sc2i | 102.15 (3) | Gd1xvi—Ge1—Sc1xvi | 0.000 (17) |
Ge1—Gd1—Sc2i | 49.75 (3) | Gd2—Ge1—Sc3iii | 70.16 (5) |
Ge3iii—Gd1—Sc2i | 114.68 (3) | Sc2i—Ge1—Sc3iii | 140.10 (6) |
Ge2iv—Gd1—Sc2i | 145.18 (3) | Gd2i—Ge1—Sc3iii | 140.10 (6) |
Ge1v—Gd1—Sc2i | 50.82 (3) | Sc2xv—Ge1—Sc3iii | 68.07 (5) |
Ge1i—Gd1—Sc2i | 48.06 (3) | Gd2xv—Ge1—Sc3iii | 68.07 (5) |
Sc3i—Gd1—Sc2i | 154.50 (3) | Ge1v—Ge1—Sc3iii | 111.92 (6) |
Sc3iii—Gd1—Sc2i | 101.62 (3) | Gd1xvi—Ge1—Sc3iii | 71.70 (5) |
Ge3i—Gd1—Gd2i | 130.59 (3) | Sc1xvi—Ge1—Sc3iii | 71.70 (5) |
Ge1ii—Gd1—Gd2i | 102.15 (3) | Gd2—Ge1—Gd1 | 140.21 (4) |
Ge1—Gd1—Gd2i | 49.75 (3) | Sc2i—Ge1—Gd1 | 72.53 (3) |
Ge3iii—Gd1—Gd2i | 114.68 (3) | Gd2i—Ge1—Gd1 | 72.53 (3) |
Ge2iv—Gd1—Gd2i | 145.18 (3) | Sc2xv—Ge1—Gd1 | 80.83 (4) |
Ge1v—Gd1—Gd2i | 50.82 (3) | Gd2xv—Ge1—Gd1 | 80.83 (4) |
Ge1i—Gd1—Gd2i | 48.06 (3) | Ge1v—Ge1—Gd1 | 63.25 (3) |
Sc3i—Gd1—Gd2i | 154.50 (3) | Gd1xvi—Ge1—Gd1 | 77.14 (2) |
Sc3iii—Gd1—Gd2i | 101.62 (3) | Sc1xvi—Ge1—Gd1 | 77.14 (2) |
Sc2i—Gd1—Gd2i | 0.00 (4) | Sc3iii—Ge1—Gd1 | 70.08 (4) |
Ge3i—Gd1—Gd2vi | 126.15 (3) | Ge3vi—Ge2—Sc2xiv | 140.05 (3) |
Ge1ii—Gd1—Gd2vi | 100.11 (3) | Ge3vi—Ge2—Gd2xiv | 140.05 (3) |
Ge1—Gd1—Gd2vi | 112.35 (3) | Sc2xiv—Ge2—Gd2xiv | 0.00 (5) |
Ge3iii—Gd1—Gd2vi | 50.84 (3) | Ge3vi—Ge2—Sc2xiii | 140.05 (3) |
Ge2iv—Gd1—Gd2vi | 49.15 (3) | Sc2xiv—Ge2—Sc2xiii | 79.86 (7) |
Ge1v—Gd1—Gd2vi | 146.68 (3) | Gd2xiv—Ge2—Sc2xiii | 79.86 (7) |
Ge1i—Gd1—Gd2vi | 48.63 (3) | Ge3vi—Ge2—Gd2xiii | 140.05 (3) |
Sc3i—Gd1—Gd2vi | 97.04 (4) | Sc2xiv—Ge2—Gd2xiii | 79.86 (7) |
Sc3iii—Gd1—Gd2vi | 100.63 (4) | Gd2xiv—Ge2—Gd2xiii | 79.86 (7) |
Sc2i—Gd1—Gd2vi | 96.57 (3) | Sc2xiii—Ge2—Gd2xiii | 0.00 (5) |
Gd2i—Gd1—Gd2vi | 96.57 (3) | Ge3vi—Ge2—Sc3xvi | 114.80 (6) |
Ge1—Gd2—Ge2vii | 92.98 (5) | Sc2xiv—Ge2—Sc3xvi | 72.27 (5) |
Ge1—Gd2—Ge1viii | 94.01 (4) | Gd2xiv—Ge2—Sc3xvi | 72.27 (5) |
Ge2vii—Gd2—Ge1viii | 150.21 (6) | Sc2xiii—Ge2—Sc3xvi | 72.27 (5) |
Ge1—Gd2—Ge2iii | 91.61 (5) | Gd2xiii—Ge2—Sc3xvi | 72.27 (5) |
Ge2vii—Gd2—Ge2iii | 93.56 (4) | Ge3vi—Ge2—Sc2xii | 62.63 (4) |
Ge1viii—Gd2—Ge2iii | 115.13 (5) | Sc2xiv—Ge2—Sc2xii | 86.39 (4) |
Ge1—Gd2—Ge1ix | 117.05 (5) | Gd2xiv—Ge2—Sc2xii | 86.39 (4) |
Ge2vii—Gd2—Ge1ix | 90.00 (5) | Sc2xiii—Ge2—Sc2xii | 138.11 (5) |
Ge1viii—Gd2—Ge1ix | 61.14 (4) | Gd2xiii—Ge2—Sc2xii | 138.11 (5) |
Ge2iii—Gd2—Ge1ix | 150.92 (6) | Sc3xvi—Ge2—Sc2xii | 139.64 (4) |
Ge1—Gd2—Ge3x | 148.48 (6) | Ge3vi—Ge2—Gd2xii | 62.63 (4) |
Ge2vii—Gd2—Ge3x | 95.19 (5) | Sc2xiv—Ge2—Gd2xii | 86.39 (4) |
Ge1viii—Gd2—Ge3x | 93.83 (5) | Gd2xiv—Ge2—Gd2xii | 86.39 (4) |
Ge2iii—Gd2—Ge3x | 57.57 (4) | Sc2xiii—Ge2—Gd2xii | 138.11 (5) |
Ge1ix—Gd2—Ge3x | 93.37 (5) | Gd2xiii—Ge2—Gd2xii | 138.11 (5) |
Ge1—Gd2—Sc3vii | 149.10 (6) | Sc3xvi—Ge2—Gd2xii | 139.64 (4) |
Ge2vii—Gd2—Sc3vii | 58.41 (5) | Sc2xii—Ge2—Gd2xii | 0.00 (7) |
Ge1viii—Gd2—Sc3vii | 105.69 (5) | Ge3vi—Ge2—Gd2iii | 62.63 (4) |
Ge2iii—Gd2—Sc3vii | 100.88 (5) | Sc2xiv—Ge2—Gd2iii | 138.11 (5) |
Ge1ix—Gd2—Sc3vii | 57.21 (4) | Gd2xiv—Ge2—Gd2iii | 138.11 (5) |
Ge3x—Gd2—Sc3vii | 54.94 (5) | Sc2xiii—Ge2—Gd2iii | 86.39 (4) |
Ge1—Gd2—Sc3iii | 58.06 (4) | Gd2xiii—Ge2—Gd2iii | 86.39 (4) |
Ge2vii—Gd2—Sc3iii | 54.33 (5) | Sc3xvi—Ge2—Gd2iii | 139.64 (4) |
Ge1viii—Gd2—Sc3iii | 148.75 (6) | Sc2xii—Ge2—Gd2iii | 77.95 (6) |
Ge2iii—Gd2—Sc3iii | 57.77 (5) | Gd2xii—Ge2—Gd2iii | 77.95 (6) |
Ge1ix—Gd2—Sc3iii | 141.16 (6) | Ge3vi—Ge2—Sc2iii | 62.63 (4) |
Ge3x—Gd2—Sc3iii | 103.67 (5) | Sc2xiv—Ge2—Sc2iii | 138.11 (5) |
Sc3vii—Gd2—Sc3iii | 105.56 (5) | Gd2xiv—Ge2—Sc2iii | 138.11 (5) |
Ge1—Gd2—Gd1viii | 59.81 (3) | Sc2xiii—Ge2—Sc2iii | 86.39 (4) |
Ge2vii—Gd2—Gd1viii | 102.14 (4) | Gd2xiii—Ge2—Sc2iii | 86.39 (4) |
Ge1viii—Gd2—Gd1viii | 57.73 (3) | Sc3xvi—Ge2—Sc2iii | 139.64 (4) |
Ge2iii—Gd2—Gd1viii | 147.65 (5) | Sc2xii—Ge2—Sc2iii | 77.95 (6) |
Ge1ix—Gd2—Gd1viii | 58.16 (3) | Gd2xii—Ge2—Sc2iii | 77.95 (6) |
Ge3x—Gd2—Gd1viii | 146.13 (5) | Gd2iii—Ge2—Sc2iii | 0.00 (7) |
Sc3vii—Gd2—Gd1viii | 111.45 (5) | Ge3vi—Ge2—Sc3 | 116.13 (6) |
Sc3iii—Gd2—Gd1viii | 110.10 (4) | Sc2xiv—Ge2—Sc3 | 69.24 (5) |
Ge1—Gd2—Sc1viii | 59.81 (3) | Gd2xiv—Ge2—Sc3 | 69.24 (5) |
Ge2vii—Gd2—Sc1viii | 102.14 (4) | Sc2xiii—Ge2—Sc3 | 69.24 (5) |
Ge1viii—Gd2—Sc1viii | 57.73 (3) | Gd2xiii—Ge2—Sc3 | 69.24 (5) |
Ge2iii—Gd2—Sc1viii | 147.65 (5) | Sc3xvi—Ge2—Sc3 | 129.07 (7) |
Ge1ix—Gd2—Sc1viii | 58.16 (3) | Sc2xii—Ge2—Sc3 | 68.88 (5) |
Ge3x—Gd2—Sc1viii | 146.13 (5) | Gd2xii—Ge2—Sc3 | 68.88 (5) |
Sc3vii—Gd2—Sc1viii | 111.45 (5) | Gd2iii—Ge2—Sc3 | 68.88 (5) |
Sc3iii—Gd2—Sc1viii | 110.10 (4) | Sc2iii—Ge2—Sc3 | 68.88 (5) |
Gd1viii—Gd2—Sc1viii | 0.000 (12) | Ge3vi—Ge2—Sc1iv | 63.16 (3) |
Ge1—Gd2—Sc2xi | 115.24 (3) | Sc2xiv—Ge2—Sc1iv | 143.07 (5) |
Ge2vii—Gd2—Sc2xi | 50.07 (3) | Gd2xiv—Ge2—Sc1iv | 143.07 (5) |
Ge1viii—Gd2—Sc2xi | 146.07 (3) | Sc2xiii—Ge2—Sc1iv | 85.07 (3) |
Ge2iii—Gd2—Sc2xi | 51.02 (3) | Gd2xiii—Ge2—Sc1iv | 85.07 (3) |
Ge1ix—Gd2—Sc2xi | 113.99 (3) | Sc3xvi—Ge2—Sc1iv | 71.06 (4) |
Ge3x—Gd2—Sc2xi | 52.25 (3) | Sc2xii—Ge2—Sc1iv | 125.53 (5) |
Sc3vii—Gd2—Sc2xi | 57.08 (3) | Gd2xii—Ge2—Sc1iv | 125.53 (5) |
Sc3iii—Gd2—Sc2xi | 57.25 (3) | Gd2iii—Ge2—Sc1iv | 73.36 (3) |
Gd1viii—Gd2—Sc2xi | 152.21 (2) | Sc2iii—Ge2—Sc1iv | 73.36 (3) |
Sc1viii—Gd2—Sc2xi | 152.21 (2) | Sc3—Ge2—Sc1iv | 135.00 (2) |
Ge1—Gd2—Gd2xi | 115.24 (3) | Ge2xvii—Ge3—Sc3xv | 113.62 (6) |
Ge2vii—Gd2—Gd2xi | 50.07 (3) | Ge2xvii—Ge3—Sc3 | 116.29 (7) |
Ge1viii—Gd2—Gd2xi | 146.07 (3) | Sc3xv—Ge3—Sc3 | 130.10 (7) |
Ge2iii—Gd2—Gd2xi | 51.02 (3) | Ge2xvii—Ge3—Sc2xviii | 59.80 (4) |
Ge1ix—Gd2—Gd2xi | 113.99 (3) | Sc3xv—Ge3—Sc2xviii | 69.05 (5) |
Ge3x—Gd2—Gd2xi | 52.25 (3) | Sc3—Ge3—Sc2xviii | 140.34 (4) |
Sc3vii—Gd2—Gd2xi | 57.08 (3) | Ge2xvii—Ge3—Gd2xviii | 59.80 (4) |
Sc3iii—Gd2—Gd2xi | 57.25 (3) | Sc3xv—Ge3—Gd2xviii | 69.05 (5) |
Gd1viii—Gd2—Gd2xi | 152.21 (2) | Sc3—Ge3—Gd2xviii | 140.34 (4) |
Sc1viii—Gd2—Gd2xi | 152.21 (2) | Sc2xviii—Ge3—Gd2xviii | 0.00 (3) |
Sc2xi—Gd2—Gd2xi | 0.00 (6) | Ge2xvii—Ge3—Sc2x | 59.80 (4) |
Ge2ii—Sc3—Ge3ix | 178.82 (9) | Sc3xv—Ge3—Sc2x | 69.05 (5) |
Ge2ii—Sc3—Ge3 | 90.52 (7) | Sc3—Ge3—Sc2x | 140.34 (4) |
Ge3ix—Sc3—Ge3 | 88.30 (6) | Sc2xviii—Ge3—Sc2x | 75.49 (6) |
Ge2ii—Sc3—Ge1xii | 87.76 (4) | Gd2xviii—Ge3—Sc2x | 75.49 (6) |
Ge3ix—Sc3—Ge1xii | 92.35 (4) | Ge2xvii—Ge3—Gd2x | 59.80 (4) |
Ge3—Sc3—Ge1xii | 95.56 (4) | Sc3xv—Ge3—Gd2x | 69.05 (5) |
Ge2ii—Sc3—Ge1iii | 87.76 (4) | Sc3—Ge3—Gd2x | 140.34 (4) |
Ge3ix—Sc3—Ge1iii | 92.35 (4) | Sc2xviii—Ge3—Gd2x | 75.49 (6) |
Ge3—Sc3—Ge1iii | 95.56 (4) | Gd2xviii—Ge3—Gd2x | 75.49 (6) |
Ge1xii—Sc3—Ge1iii | 168.04 (8) | Sc2x—Ge3—Gd2x | 0.00 (4) |
Ge2ii—Sc3—Ge2 | 89.64 (6) | Ge2xvii—Ge3—Gd1xix | 132.513 (19) |
Ge3ix—Sc3—Ge2 | 91.54 (7) | Sc3xv—Ge3—Gd1xix | 73.78 (4) |
Ge3—Sc3—Ge2 | 179.85 (9) | Sc3—Ge3—Gd1xix | 73.09 (4) |
Ge1xii—Sc3—Ge2 | 84.44 (4) | Sc2xviii—Ge3—Gd1xix | 83.28 (3) |
Ge1iii—Sc3—Ge2 | 84.44 (4) | Gd2xviii—Ge3—Gd1xix | 83.28 (3) |
Ge2ii—Sc3—Sc2xiii | 124.88 (6) | Sc2x—Ge3—Gd1xix | 141.76 (5) |
Ge3ix—Sc3—Sc2xiii | 56.01 (5) | Gd2x—Ge3—Gd1xix | 141.76 (5) |
Ge3—Sc3—Sc2xiii | 127.54 (6) | Ge2xvii—Ge3—Sc1xix | 132.513 (19) |
Ge1xii—Sc3—Sc2xiii | 120.23 (7) | Sc3xv—Ge3—Sc1xix | 73.78 (4) |
Ge1iii—Sc3—Sc2xiii | 54.72 (4) | Sc3—Ge3—Sc1xix | 73.09 (4) |
Ge2—Sc3—Sc2xiii | 52.35 (4) | Sc2xviii—Ge3—Sc1xix | 83.28 (3) |
Ge2ii—Sc3—Gd2xiii | 124.88 (6) | Gd2xviii—Ge3—Sc1xix | 83.28 (3) |
Ge3ix—Sc3—Gd2xiii | 56.01 (5) | Sc2x—Ge3—Sc1xix | 141.76 (5) |
Ge3—Sc3—Gd2xiii | 127.54 (6) | Gd2x—Ge3—Sc1xix | 141.76 (5) |
Ge1xii—Sc3—Gd2xiii | 120.23 (7) | Gd1xix—Ge3—Sc1xix | 0.000 (17) |
Ge1iii—Sc3—Gd2xiii | 54.72 (4) | Ge2xvii—Ge3—Gd1viii | 132.513 (19) |
Ge2—Sc3—Gd2xiii | 52.35 (4) | Sc3xv—Ge3—Gd1viii | 73.78 (4) |
Sc2xiii—Sc3—Gd2xiii | 0.00 (3) | Sc3—Ge3—Gd1viii | 73.09 (4) |
Ge2ii—Sc3—Sc2xiv | 124.88 (6) | Sc2xviii—Ge3—Gd1viii | 141.76 (5) |
Ge3ix—Sc3—Sc2xiv | 56.01 (5) | Gd2xviii—Ge3—Gd1viii | 141.76 (5) |
Ge3—Sc3—Sc2xiv | 127.54 (6) | Sc2x—Ge3—Gd1viii | 83.28 (3) |
Ge1xii—Sc3—Sc2xiv | 54.72 (4) | Gd2x—Ge3—Gd1viii | 83.28 (3) |
Ge1iii—Sc3—Sc2xiv | 120.23 (7) | Gd1xix—Ge3—Gd1viii | 94.96 (4) |
Ge2—Sc3—Sc2xiv | 52.35 (4) | Sc1xix—Ge3—Gd1viii | 94.96 (4) |
Sc2xiii—Sc3—Sc2xiv | 65.84 (6) | Ge2xvii—Ge3—Sc1viii | 132.513 (19) |
Gd2xiii—Sc3—Sc2xiv | 65.84 (6) | Sc3xv—Ge3—Sc1viii | 73.78 (4) |
Ge2ii—Sc3—Gd2xiv | 124.88 (6) | Sc3—Ge3—Sc1viii | 73.09 (4) |
Ge3ix—Sc3—Gd2xiv | 56.01 (5) | Sc2xviii—Ge3—Sc1viii | 141.76 (5) |
Ge3—Sc3—Gd2xiv | 127.54 (6) | Gd2xviii—Ge3—Sc1viii | 141.76 (5) |
Ge1xii—Sc3—Gd2xiv | 54.72 (4) | Sc2x—Ge3—Sc1viii | 83.28 (3) |
Ge1iii—Sc3—Gd2xiv | 120.23 (7) | Gd2x—Ge3—Sc1viii | 83.28 (3) |
Ge2—Sc3—Gd2xiv | 52.35 (4) | Gd1xix—Ge3—Sc1viii | 94.96 (4) |
Sc2xiii—Sc3—Gd2xiv | 65.84 (6) | Sc1xix—Ge3—Sc1viii | 94.96 (4) |
Gd2xiii—Sc3—Gd2xiv | 65.84 (6) | Gd1viii—Ge3—Sc1viii | 0.000 (17) |
Sc2xiv—Sc3—Gd2xiv | 0.00 (3) | Ge2xvii—Ge3—Gd1iii | 64.56 (3) |
Ge2ii—Sc3—Sc2xii | 53.40 (4) | Sc3xv—Ge3—Gd1iii | 134.19 (2) |
Ge3ix—Sc3—Sc2xii | 127.47 (6) | Sc3—Ge3—Gd1iii | 71.12 (4) |
Ge3—Sc3—Sc2xii | 126.76 (6) | Sc2xviii—Ge3—Gd1iii | 124.12 (5) |
Ge1xii—Sc3—Sc2xii | 51.79 (3) | Gd2xviii—Ge3—Gd1iii | 124.12 (5) |
Ge1iii—Sc3—Sc2xii | 117.23 (7) | Sc2x—Ge3—Gd1iii | 72.92 (3) |
Ge2—Sc3—Sc2xii | 53.35 (4) | Gd2x—Ge3—Gd1iii | 72.92 (3) |
Sc2xiii—Sc3—Sc2xii | 105.69 (6) | Gd1xix—Ge3—Gd1iii | 144.10 (4) |
Gd2xiii—Sc3—Sc2xii | 105.69 (6) | Sc1xix—Ge3—Gd1iii | 144.10 (4) |
Sc2xiv—Sc3—Sc2xii | 71.49 (4) | Gd1viii—Ge3—Gd1iii | 77.357 (18) |
Gd2xiv—Sc3—Sc2xii | 71.49 (4) | Sc1viii—Ge3—Gd1iii | 77.357 (18) |
Ge2ii—Sc3—Gd2iii | 53.40 (4) |
Symmetry codes: (i) −x+3/2, −y+1, z−1/2; (ii) x+1/2, y, −z+1/2; (iii) −x+1, −y+1, −z+1; (iv) −x+1, −y+1, −z; (v) −x+2, −y+1, −z+1; (vi) x, y, z−1; (vii) −x+1/2, −y+1, z+1/2; (viii) −x+3/2, −y+1, z+1/2; (ix) x−1/2, y, −z+3/2; (x) −x+1, −y+1, −z+2; (xi) x, −y+1/2, z; (xii) −x+1, y+1/2, −z+1; (xiii) −x+1/2, −y+1, z−1/2; (xiv) −x+1/2, y+1/2, z−1/2; (xv) x+1/2, y, −z+3/2; (xvi) x−1/2, y, −z+1/2; (xvii) x, y, z+1; (xviii) −x+1, y+1/2, −z+2; (xix) −x+3/2, y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | Gd2Sc3Ge4 |
Mr | 739.74 |
Crystal system, space group | Orthorhombic, Pnma |
Temperature (K) | 298 |
a, b, c (Å) | 7.2445 (13), 14.101 (3), 7.4930 (14) |
V (Å3) | 765.4 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 34.91 |
Crystal size (mm) | 0.06 × 0.05 × 0.01 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.127, 0.705 |
No. of measured, independent and observed [I > 2s(I)] reflections | 6182, 958, 816 |
Rint | 0.070 |
(sin θ/λ)max (Å−1) | 0.665 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.066, 1.05 |
No. of reflections | 958 |
No. of parameters | 49 |
Δρmax, Δρmin (e Å−3) | 2.20, −1.44 |
Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).
Continuing our efforts in mixed rare-earth systems bearing the formula (R1-xR'x)5T4, where T = Si, Ge, Ga, Sn, we have studied the effect of substitution of Gd by nonmagnetic Sc. Gd2Sc3Ge4 crystallizes in the orthorhombic Pu5Rh4-type structure (Cromer, 1977). Two 32434 nets built up of Gd and Sc atoms are placed over one another to form two-dimensional slabs with additional Sc atoms in pseudo-cubic coordination and Ge atoms in trigonal prismatic voids (Fig. 1).
The two metal sites situated at the edges of the cube (M1 and M2) exhibit mixed site occupancies, with Gd (the larger atom; Shannon, 1976) having a preference for the M1 site and Sc (the smaller atom; Shannon, 1976) having a preference for the M2 site. The M3 site is completely occupied by Sc atom. This disordered model which introduces two additional refinement parameters yields a statistically significant improvement over various ordered models, at the 0.5% significance level according to a Hamilton's significance test on the crystallographic R factor (Hamilton, 1965).
The Ge1–Ge1 distances are intermediate between those in Gd5Ga2Ge2 [2.741 (1) Å; Gd5Si4-type (Holtzberg et al., 1967)] and Gd5Ga0.7Ge3.3 [3.461 (5) Å; Sm5Ge4-type (Smith et al., 1967)] (Mozharivskyj et al., 2003).