element

Li

Na

K

Cs

electronegativity

0.98

0.93

0.82

0.79

Melting point

180.54

97.720

63.380

28.440

Vaporisation point

1342

882.9

758.9

671

Electronic affinity

0.618

0.547

0.502

0.472

Ionisation energy

5 eV

5.139

4.341

3.894

Thermal conductivity

85 W/mK

140

100

36

Specific heat

1230 J/Kg∙K

757

242

Ref. structure

BCC