{
  "alternatives": [],
  "meta": {
    "api_version": "v1",
    "attribution": "lithium-niobate.com data compiled by Wentao Jiang; cite the original sources listed per value.",
    "data_version": "0.1.0",
    "documentation": "https://lithium-niobate.com/api/openapi.json",
    "license": {
      "id": "CC-BY-4.0",
      "name": "Creative Commons Attribution 4.0 International",
      "url": "https://creativecommons.org/licenses/by/4.0/"
    },
    "tensor": "elastic-stiffness-cE",
    "variant": "cln"
  },
  "recommended": {
    "conditions": {
      "electrical_boundary": "E"
    },
    "consistency": [
      {
        "check": "piezo-stiffened longitudinal velocity along Z, sqrt((c33 + e33^2/eps33^S)/rho), kushibiki1999 constants and density",
        "result": "7328.6 m/s (unstiffened 7102.1 m/s); measured 7328.20 m/s (kushibiki1999 Table II)",
        "status": "C"
      }
    ],
    "default": true,
    "frame": {
      "convention": "unstated",
      "handedness": "right",
      "setting": "crystal-physics",
      "x": "a axis, perpendicular to a mirror plane",
      "y": "in a mirror plane",
      "z": "polar c axis",
      "z_sign_definition": "not stated in this record; tensor form matches this frame by symmetry"
    },
    "full": [
      [
        [
          [
            198.86,
            0.0,
            0.0
          ],
          [
            0.0,
            54.67,
            7.83
          ],
          [
            0.0,
            7.83,
            67.99
          ]
        ],
        [
          [
            0.0,
            72.095,
            7.83
          ],
          [
            72.095,
            0.0,
            0.0
          ],
          [
            7.83,
            0.0,
            0.0
          ]
        ],
        [
          [
            0.0,
            7.83,
            59.85
          ],
          [
            7.83,
            0.0,
            0.0
          ],
          [
            59.85,
            0.0,
            0.0
          ]
        ]
      ],
      [
        [
          [
            0.0,
            72.095,
            7.83
          ],
          [
            72.095,
            0.0,
            0.0
          ],
          [
            7.83,
            0.0,
            0.0
          ]
        ],
        [
          [
            54.67,
            0.0,
            0.0
          ],
          [
            0.0,
            198.86,
            -7.83
          ],
          [
            0.0,
            -7.83,
            67.99
          ]
        ],
        [
          [
            7.83,
            0.0,
            0.0
          ],
          [
            0.0,
            -7.83,
            59.85
          ],
          [
            0.0,
            59.85,
            0.0
          ]
        ]
      ],
      [
        [
          [
            0.0,
            7.83,
            59.85
          ],
          [
            7.83,
            0.0,
            0.0
          ],
          [
            59.85,
            0.0,
            0.0
          ]
        ],
        [
          [
            7.83,
            0.0,
            0.0
          ],
          [
            0.0,
            -7.83,
            59.85
          ],
          [
            0.0,
            59.85,
            0.0
          ]
        ],
        [
          [
            67.99,
            0.0,
            0.0
          ],
          [
            0.0,
            67.99,
            0.0
          ],
          [
            0.0,
            0.0,
            234.18
          ]
        ]
      ]
    ],
    "id": "elastic-stiffness-cE/cln/kushibiki1999",
    "independent": {
      "c11": {
        "uncertainty": {
          "type": "stated",
          "value": 0.03
        },
        "value": 198.86
      },
      "c12": {
        "uncertainty": {
          "type": "stated",
          "value": 0.04
        },
        "value": 54.67
      },
      "c13": {
        "uncertainty": {
          "type": "stated",
          "value": 0.55
        },
        "value": 67.99
      },
      "c14": {
        "uncertainty": {
          "type": "stated",
          "value": 0.02
        },
        "value": 7.83
      },
      "c33": {
        "uncertainty": {
          "type": "stated",
          "value": 0.75
        },
        "value": 234.18
      },
      "c44": {
        "uncertainty": {
          "type": "stated",
          "value": 0.01
        },
        "value": 59.85
      }
    },
    "kind": "tensor",
    "name": "Elastic stiffness at constant electric field",
    "notes": "The source also lists c66 = 72.09 +- 0.02 GPa; the 3m relation (c11 - c12)/2 gives 72.095. In the same table LiTaO3 has c14 = -10.75 GPa.",
    "provenance": {
      "source_id": "kushibiki1999",
      "status": "P",
      "transcribed": "2026-10-25"
    },
    "public": true,
    "rank": 4,
    "scale": 1,
    "symbol": "c^E",
    "symmetry_form": {
      "form": [
        [
          "c11",
          "c12",
          "c13",
          "c14",
          "0",
          "0"
        ],
        [
          "c12",
          "c11",
          "c13",
          "-c14",
          "0",
          "0"
        ],
        [
          "c13",
          "c13",
          "c33",
          "0",
          "0",
          "0"
        ],
        [
          "c14",
          "-c14",
          "0",
          "c44",
          "0",
          "0"
        ],
        [
          "0",
          "0",
          "0",
          "0",
          "c44",
          "c14"
        ],
        [
          "0",
          "0",
          "0",
          "0",
          "c14",
          "(c11-c12)/2"
        ]
      ],
      "mirror": "x = 0 plane (x perpendicular to the mirror, z polar)",
      "point_group": "3m",
      "relations": [
        "c22 = c11",
        "c23 = c13",
        "c24 = -c14",
        "c55 = c44",
        "c56 = c14",
        "c66 = (c11 - c12)/2"
      ]
    },
    "tensor": "elastic-stiffness-cE",
    "unit": {
      "display": "GPa",
      "qudt": "http://qudt.org/vocab/unit/GigaPA",
      "ucum": "GPa"
    },
    "variant": "cln",
    "variant_note": "SAW-grade congruent",
    "voigt": [
      [
        198.86,
        54.67,
        67.99,
        7.83,
        0.0,
        0.0
      ],
      [
        54.67,
        198.86,
        67.99,
        -7.83,
        0.0,
        0.0
      ],
      [
        67.99,
        67.99,
        234.18,
        0.0,
        0.0,
        0.0
      ],
      [
        7.83,
        -7.83,
        0.0,
        59.85,
        0.0,
        0.0
      ],
      [
        0.0,
        0.0,
        0.0,
        0.0,
        59.85,
        7.83
      ],
      [
        0.0,
        0.0,
        0.0,
        0.0,
        7.83,
        72.095
      ]
    ],
    "voigt_convention": {
      "full_from_voigt": "C_ijkl = c_IJ, I = V(ij), J = V(kl)",
      "order": [
        "xx",
        "yy",
        "zz",
        "yz",
        "xz",
        "xy"
      ],
      "shear_strain": "engineering"
    }
  },
  "recommended_note": null,
  "spread": {
    "c11": {
      "max": 198.86,
      "min": 198.86,
      "n_records": 1
    },
    "c12": {
      "max": 54.67,
      "min": 54.67,
      "n_records": 1
    },
    "c13": {
      "max": 67.99,
      "min": 67.99,
      "n_records": 1
    },
    "c14": {
      "max": 7.83,
      "min": 7.83,
      "n_records": 1
    },
    "c33": {
      "max": 234.18,
      "min": 234.18,
      "n_records": 1
    },
    "c44": {
      "max": 59.85,
      "min": 59.85,
      "n_records": 1
    }
  }
}