Table 1 Selected interatomic distances of untreated chlormayenite² and annealed crystals at 573 K and 773 K and 1073 K.

Ca1

O1 × 2

2.386 (4)

2.3821 (3)

2.3743 (4)

2.3738 (4)

O1 × 2

2.496 (4)

2.4924 (5)

2.5027 (11)

2.5042 (15)

O2 × 2

2.416 (4)

2.4138 (3)

2.4198 (4)

2.4142 (5)

O2a* × 2

2.256 (4)

2.254 (4)

—

—

O2a* × 2

2.485 (5)

2.476 (4)

—

—

^WCl

2.854 (2)

2.8508 (4)

2.8508 (12)

2.8386 (17)

Ca2

O1 × 2

2.3855 (11)

2.3829 (11)

2.3826 (17)

O1 × 2

2.786 (11)

2.845 (8)

2.837 (14)

O2 × 2

2.3584 (12)

2.3600 (7)

2.3564 (11)

^WOH

—

2.451 (9)

2.450 (15)

T1

O1 × 3

1.790 (4)

1.7864 (3)

1.7842 (4)

1.7790 (5)

O2*

1.714 (8)

1.7130 (7)

1.7333 (8)

1.7298 (8)

O2a* × 3

2.098 (5)

2.099 (4)

—

—

T2

O1 × 4

1.746 (4)

1.7440 (3)

1.7465 (4)

1.7422 (4)