Table 1 The optimized lattice constant and cell volume for LaMg₂Ni, LaMg₂NiH_4.5, LaMg₂NiH₇ and their corresponding Co- and Pd-containing compounds, in comparison with the available experimental/theoretical data.

LaMg₂Ni

4.426 (4.227)

10.178 (10.303)

8.155 (8.360)

90⁰ (90⁰)

734.83 (728.02)

^15,20

LaMg₂NiH_4.5

8.673 (8.602)

7.982 (7.937)

6.151 (6.114)

99.66⁰ (99.53⁰)

839.566 (823.334)

¹⁷

LaMg₂NiH₇

14.102 (13.979)

4.719 (4.703)

16.155 (16.025)

125.2⁰ (125.24⁰)

878.494 (860.39)

¹⁵

LaMg₂Ni–Co

4.207 (4.210)

10.105 (10.278)

8.340 (8.36)

90.0⁰ (…)

733.158 (723.38)

²⁰

LaMg₂Ni–Pd

4.363 (4.24)

10.258 (10.326)

8.259 (8.346)

90.02⁰ (…)

739.291 (730.80)

²⁰

LaMg₂NiH_4.5–Co

8.889 (…)

15.364 (…)

6.127 (…)

102.398⁰ (…)

817.306 (…)

…

LaMg₂NiH_4.5–Pd

8.639 (…)

16.172 (…)

6.154 (…)

99.23⁰ (…)

848.577 (…)

…

LaMg₂NiH₇–Co

14.028 (13.959)

4.701 (4.719)

16.151 (16.064)

125.27⁰ (124.89⁰)

869.052 (867.89)

²⁰

LaMg₂NiH₇–Pd

14.148 (14.003)

4.728 (4.723)

16.177 (16.096)

125.16⁰ (124.79⁰)

884.62 (874.13)

²⁰