Table 2 Classical4,5,6,7,8,9,18,] and non-classical new calcite twins and their smallest EBSD misorientation angle Φ and corresponding axis. Refer to the supplementary material for a graphical illustration. Acronym sor = systematically reoccurring orientation relationship. The so-called a-type twins are “twins in twins”, the two sequential classical twin operations are indicated.
Twin Name | Notation | Twin mirror plane or coincidence site lattice plane (CSLP) | 180° Twin axis (pole to twin plane) | EBSD misorientation angle φ and misorientation axis | |
|---|---|---|---|---|---|
{001} contact twin or penetration twin | Vector | {001} | <001> | 60° | <001> |
Bravais | {0001} | <0001> | <0001> | ||
e-twin | Vector | (018) | 0.6° from [121] | 78.1° | 0.7 ° from [4 2 1] |
Bravais | (0 1 −1 8) | 0.6° from [0 1 −1 1] | 0.7 ° from [2 0 −2 1] | ||
r-twin | Vector | (104) | 0.7° from [421] | 103.9° | 0.6 ° from [4 −4 1] |
Bravais | (1 0 −1 4) | 0.7° from [2 0 2 1] | 0.6 ° from [4 −4 0 1] | ||
f-twin | Vector | (012) | 0.6 ° from [4 8 1] | 78.8° | [2 −2 1] |
Bravais | (0 1 −1 2) | 0.6° from [0 4 −4 1] | [2 –2 0 1] | ||
a-type r\(\otimes\)e | Vector | first e then r | 38.2° | [1 0 0] | |
Bravais | [2 –1 −1 0] | ||||
a-type f\(\otimes\)r | Vector | first r then f | 35.5° | [100] | |
Bravais | [2 −1 −1 0] | ||||
{108} Pokroy | Vector | (108) | 0.6 ° from [2 1 1] | 78.1° | 0.7 ° from [2 −2 1] |
Bravais | (1 0 −1 8) | 0.6° from [ 1 0 –1 1] | 0.7 ° from [2 –2 0 1 ] | ||
Vector | 0° from [8 4 –1] | ||||
Bravais | 0° from [4 0 −4 −1] | ||||
sor <6–6 1> | Vector | 5.1° from (129) | 2.3° from [4 5 1] | 76.6 | [6 −6 1] |
Bravais | 5.1° from (1 2 −3 9) | 2.3° from [1 2 −3 1] | [6 −6 0 1] | ||
sor <9 9 1> | Vector | CSLP (−7 5 18) | – | 78.2 | [9 9 1] |
Bravais | CSLP (−7 5 2 18) | – | [3 3 −6 1] | ||
