Lithium and magnesium have a diagonal relationship due to their similar atomic radii, so that they show some similarities.
lˈɪθiəm ænd mæɡnˈiːziəm hæv ɐ daɪˈæɡənəl ɹᵻlˈeɪʃənʃˌɪp dˈuː tə ðɛɹ sˈɪmɪlɚɹ ɐtˈɑːmɪk ɹˈeɪdɪˌaɪ, sˌoʊ ðæt ðeɪ ʃˈoʊ sˌʌm sˌɪmɪlˈæɹᵻɾiz.