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NIST High Temp. Superconducting Materials (HTS) Database:

NIST Standard Reference Database 62

Last Update to Data Content: 1996

DOI: https://doi.org/10.18434/T4KP8J

Bibliographic Information

Title: Reference Relations for the Evaluation of the Materials Properties of Orthorhombic YBa2Cu3Ox Superconductors
Author(s): R.G. Munro and H. Chen
Publication: Journal of the American Ceramic Society Volume: 79 Issue: 3 Year: 1996 Page(s): 603-608
Editor(s): Not Available
Publisher: American Ceramic Society
Language: English
Notes: Not Available
Keywords: Material Specification, Density (mass), Crystallography, Critical Temperature, Thermal Expansion

Materials and Properties

Y:123; [Y-Ba-Cu-O]
Material Specification for Y:123; [Y-Ba-Cu-O] Process: Solid State Reaction
Notes: "The objective of the present work is to synthesize several independent studies of oxygen and temperature dependencies for orthorhombic YBa2Cu3Ox (Y:123)... Attention is focused on specimens that were processed by solid-state reaction methods in which the maximum processing temperature was in the range 900 °C to 960 °C. Oxygen contents were typically adjusted by subsequent heat treatments at temperatures in the range 400 °C to 700 °C, sometimes followed by quenching in liquid nitrogen. The approach taken here is to develop empirical relations using independent sets of studies for each property, and then to compare the relations using additional independent results."
Formula: YBa2Cu3Ox
Informal Name: Y:123
Chemical Family: Y-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer:
Commercial Name:
Production Date:
Lot Number:
Production Form:

Density (mass) for Y:123; [Y-Ba-Cu-O]
x of Ox (formula units) Temperature (K) Density (g cm-3)
6.9 10 6.415
6.9 20 6.414
6.9 30 6.414
6.9 40 6.413
6.9 50 6.412
6.9 60 6.412
6.9 80 6.410
6.9 100 6.408
6.9 120 6.406
6.9 140 6.403
6.9 160 6.400
6.9 180 6.397
6.9 200 6.393
6.9 225 6.389
6.9 250 6.383
6.9 275 6.378
6.9 300 6.372
Measurement Method: Lattice expansion analysis
"Studies of the dependence of the lattice parameters on oxygen content have not exhibited anything more exotic than the linear dependence... which was... fitted on the interval 6.35 ≤ x ≤ 7.0 by the least-squares method, producing, for T = 296 K, the relations 
                a[σ] = 4.1696 - 0.0506 x ± 0.13%
                b[σ] = 3.6830 + 0.0294 x ± 0.15%
                c[σ] = 12.641 - 0.1378 x ± 0.16%
... Studies of the temperature dependencies of the lattice parameters are not as prevalent as studies of the composition dependence. ... The present exercise, therefore, was restricted to YBa2Cu3O6.9... independent sets of data on the linear coefficient of thermal expansion of YBa2Cu3O6.9, obtained using high-resolution dilatometry, were used to test the validity of the lattice parameter vs temperature relations. ...the least-squares fits on the interval 5 K ≤ T ≤ 300 K... resulted in the relations 
                a[σ] = 3.8112 - 0.0001947 (T/100)
                       + 0.0008585 (T/100)2 ± 0.15%
                b[σ] = 3.8803 - 0.005280 (T/100)
                       + 0.0005841 (T/100)2 ±0.18%
                c[σ] = 11.634 + 0.00338 (T/100) + 0.00668 (T/100)2
                       - 0.00095 (T/100)3 ± 0.17%
...the linear coefficient of thermal expansion, αL, for axis L... may be estimated... by differentiating with respect to temperature to obtain 
            αa[10-6 K-1] = -0.511 + 4.505 (T/100) ± ua
            αb[10-6 K-1] = -1.361 + 3.011 (T/100) ± ub
            αc[10-6 K-1] = 2.907 + 11.477 (T/100)
                       - 2.459 (T/100)2 ± uc
where... ua = 2% for T > 100 K and 30% for T < 100 K; ub = 3% for T > 125 K and 23% for T < 125 K; and uc = 10% for T > 75 K and 42% for T < 75 K. The average of (these) relations... may be taken as the estimate of the linear coefficient of thermal expansion for isotropic polycrystalline samples: α [10-6 K-1] = 0.345 + 6.331 (T/100) - 0.82 (T/100)2 ± u where u is approximately 7% for T > 100 K and 36% for T < 100 K. (The lattice parameters) and the molar formula for the material permit the density of single-crystal YBa2Cu3O6.9 to be computed as a function of temperature. Density[g/cm3] = 6.415 - 0.0034 (T/100) - 0.0037 (T/100)2 ± 0.5%"

Cautions: Validated Data
Crystallography for Y:123; [Y-Ba-Cu-O]
Crystal System: Orthorhombic
Formula Units per Cell: 1
Space Group: Pmmm
Cell Parameters
x of Ox (formula units) Temp K a Å b Å c Å
6.4 296 3.846 3.871 11.76
6.5 296 3.841 3.874 11.75
6.6 296 3.836 3.877 11.73
6.8 296 3.826 3.883 11.70
7.0 296 3.815 3.889 11.68
6.9 10 3.811 3.880 11.63
6.9 20 3.811 3.880 11.63
6.9 30 3.811 3.880 11.64
6.9 40 3.811 3.880 11.64
6.9 50 3.811 3.880 11.64
6.9 60 3.811 3.880 11.64
6.9 80 3.812 3.880 11.64
6.9 100 3.812 3.880 11.64
6.9 120 3.812 3.881 11.65
6.9 140 3.813 3.881 11.65
6.9 160 3.813 3.881 11.65
6.9 180 3.814 3.881 11.66
6.9 200 3.814 3.882 11.66
6.9 225 3.815 3.882 11.66
6.9 250 3.816 3.883 11.67
6.9 275 3.817 3.883 11.67
6.9 300 3.818 3.884 11.68
Measurement Method: Lattice expansion analysis
"Studies of the dependence of the lattice parameters on oxygen content have not exhibited anything more exotic than the linear dependence... which was... fitted on the interval 6.35 ≤ x ≤ 7.0 by the least-squares method, producing, for T = 296 K, the relations a[σ] = 4.1696 - 0.0506 x ± 0.13% b[σ] = 3.6830 + 0.0294 x ± 0.15% c[σ] = 12.641 - 0.1378 x ± 0.16% ... Studies of the temperature dependencies of the lattice parameters are not as prevalent as studies of the composition dependence. ... The present exercise, therefore, was restricted to YBa2Cu3O6.9... independent sets of data on the linear coefficient of thermal expansion of YBa2Cu3O6.9, obtained using high-resolution dilatometry, were used to test the validity of the lattice parameter vs temperature relations. ...the least-squares fits on the interval 5 K ≤ T ≤ 300 K... resulted in the relations 
                a[σ] = 3.8112 - 0.0001947 (T/100)
                       + 0.0008585 (T/100)2 ± 0.15%
                b[σ] = 3.8803 - 0.005280 (T/100)
                       + 0.0005841 (T/100)2 ±0.18%
                c[σ] = 11.634 + 0.00338 (T/100) + 0.00668 (T/100)2
                       - 0.00095 (T/100)3 ± 0.17%
...the linear coefficient of thermal expansion, αL, for axis L... may be estimated... by differentiating with respect to temperature to obtain 
    αa[10-6 K-1] = -0.511 + 4.505 (T/100) ± ua
    αb[10-6 K-1] = -1.361 + 3.011 (T/100) ± ub
    αc[10-6 K-1] = 2.907 + 11.477 (T/100)
                       - 2.459 (T/100)2 ± uc
where... ua = 2% for T > 100 K and 30% for T < 100 K; ub = 3% for T > 125 K and 23% for T < 125 K; and uc = 10% for T > 75 K and 42% for T < 75 K. The average of (these) relations... may be taken as the estimate of the linear coefficient of thermal expansion for isotropic polycrystalline samples: α [10-6 K-1] = 0.345 + 6.331 (T/100) - 0.82 (T/100)2 ± u where u is approximately 7% for T > 100 K and 36% for T < 100 K. (The lattice parameters) and the molar formula for the material permit the density of single-crystal YBa2Cu3O6.9 to be computed as a function of temperature. Density[g/cm3] = 6.415 - 0.0034 (T/100) - 0.0037 (T/100)2 ± 0.5%"

Cautions: Validated Data
Critical Temperature for Y:123; [Y-Ba-Cu-O]
x of Ox (formula units) Critical Temperature (K)
6.40 28.8
6.42 32.6
6.44 37.3
6.46 42.3
6.48 47.0
6.50 50.8
6.52 53.6
6.54 55.5
6.56 56.7
6.58 57.6
6.60 58.3
6.62 59.0
6.64 60.0
6.66 61.5
6.68 63.9
6.70 67.3
6.72 71.8
6.74 76.6
6.76 81.1
6.78 84.5
6.80 86.8
6.82 88.2
6.84 89.1
6.86 89.6
6.88 89.9
6.90 90.1
6.92 90.3
6.94 90.4
Measurement Method: Critical temperature analysis
"In single-phase, homogeneous samples, the critical temperature of Y:123 exhibits a well-noted two-plateau dependence on oxygen content. ... An interpolation formula that mimics the dual plateau regions was fitted on the interval 6.4 ≤ x ≤ 6.95 by the least-squares method to obtain the empirical relation Tc[K] = 89.5 + 4.37(x - 6.73) - 30.57/[1 + exp{31.65(x - 6.73)}] - 35.79/[1 + exp{27.84(x - 6.45)}] which gives the critical temperature in kelvins as a function of the amount of oxygen expressed in formula units. Based on the standard error of the fit, the combined standard uncertainty for Tc obtained from (this) relation ... is ±3 K for x ≥ 6.5 and ±5 K for x < 6.5."

Cautions: Validated Data
Thermal Expansion for Y:123; [Y-Ba-Cu-O]
x of Ox (formula units) Crystal Axis () Temperature (K) Thermal Expansion (10-6 K-1)
6.9 a 50 1.7
6.9 a 60 2.2
6.9 a 80 3.1
6.9 a 100 4.0
6.9 a 120 4.9
6.9 a 140 5.8
6.9 a 160 6.7
6.9 a 180 7.6
6.9 a 200 8.5
6.9 b 50 0.1
6.9 b 60 0.4
6.9 b 80 1.0
6.9 b 100 1.7
6.9 b 120 2.3
6.9 b 140 2.9
6.9 b 160 3.5
6.9 b 180 4.1
6.9 b 200 4.7
6.9 c 50 8.0
6.9 c 60 8.9
6.9 c 80 10.5
6.9 c 100 11.9
6.9 c 120 13.1
6.9 c 140 14.2
6.9 c 160 15.0
6.9 c 180 15.6
6.9 c 200 16.0
6.9 isotropic 50 3.3
6.9 isotropic 60 3.8
6.9 isotropic 80 4.9
6.9 isotropic 100 5.9
6.9 isotropic 120 6.8
6.9 isotropic 140 7.6
6.9 isotropic 160 8.4
6.9 isotropic 180 9.1
6.9 isotropic 200 9.7
6.9 isotropic 225 10.4
6.9 isotropic 250 11.0
6.9 isotropic 275 11.6
6.9 isotropic 300 12.0
Measurement Method: Lattice expansion analysis
"Studies of the dependence of the lattice parameters on oxygen content have not exhibited anything more exotic than the linear dependence... which was... fitted on the interval 6.35 ≤ x ≤ 7.0 by the least-squares method, producing, for T = 296 K, the relations a[σ] = 4.1696 - 0.0506 x ± 0.13% b[σ] = 3.6830 + 0.0294 x ± 0.15% c[σ] = 12.641 - 0.1378 x ± 0.16% ... Studies of the temperature dependencies of the lattice parameters are not as prevalent as studies of the composition dependence. ... The present exercise, therefore, was restricted to YBa2Cu3O6.9... independent sets of data on the linear coefficient of thermal expansion of YBa2Cu3O6.9, obtained using high-resolution dilatometry, were used to test the validity of the lattice parameter vs temperature relations. ...the least-squares fits on the interval 5 K ≤ T ≤ 300 K... resulted in the relations 
                a[σ] = 3.8112 - 0.0001947 (T/100)
                       + 0.0008585 (T/100)2 ± 0.15%
                b[σ] = 3.8803 - 0.005280 (T/100)
                       + 0.0005841 (T/100)2 ±0.18%
                c[σ] = 11.634 + 0.00338 (T/100) + 0.00668 (T/100)2
                       - 0.00095 (T/100)3 ± 0.17%
...the linear coefficient of thermal expansion, αL, for axis L... may be estimated... by differentiating with respect to temperature to obtain 
        αa[10-6 K-1] = -0.511 + 4.505 (T/100) ± ua
        αb[10-6 K-1] = -1.361 + 3.011 (T/100) ± ub
        αc[10-6 K-1] = 2.907 + 11.477 (T/100)
                       - 2.459 (T/100)2 ± uc
where... ua = 2% for T > 100 K and 30% for T < 100 K; ub = 3% for T > 125 K and 23% for T < 125 K; and uc = 10% for T > 75 K and 42% for T < 75 K. The average of (these) relations... may be taken as the estimate of the linear coefficient of thermal expansion for isotropic polycrystalline samples: α [10-6 K-1] = 0.345 + 6.331 (T/100) - 0.82 (T/100)2 ± u where u is approximately 7% for T > 100 K and 36% for T < 100 K. (The lattice parameters) and the molar formula for the material permit the density of single-crystal YBa2Cu3O6.9 to be computed as a function of temperature. Density[g/cm3] = 6.415 - 0.0034 (T/100) - 0.0037 (T/100)2 ± 0.5%"

Cautions: Validated Data