Two dimensional mappings on superconductive elements A and AB compounds are constructed by using the valence electron parameters (the difference between pseudopotential radii (
r (
s),
r (
p) and
r (
d)) of s and p electrons or of s and d electrons,
Δ(
sp) or
Δ(
sd), and the orbital electronegativity of s electron,
χ(
s)=(
Z/
r (
s))
1/2, where
Z is valence) as the coordinates. From the relation of band gap against
χ(
s), the change of metal to semiconductor in sp-bonded elemental substances occurs at the threshold value of (
Z/
r (
s))
1/2=
2.098. It is found that the boundary for superconductivity in sp-bonded elemental substances and AB compounds appears around (
Z/
r (
s))
1/2≈
2.3. On the other hand, superconductivity appears in the region with higher (
Z/
r (
s))
1/2 value in the transition metals and AB compounds containing transition metals. Lower limit in the abscissa scale is observed around (
Z/
r (
s))
1/2=
1.3, suggesting the limitation due to electron density in metallic substances and AB compounds. Non-superconducting late 3d transition elements are clearly divided by a polynomial curve. Non-superconducting sp-bonded AB compounds are well separately placed in the region with higher (
Z/
r (
s))
1/2 value than 2.3 and lower
Δ(
sp) value than 0.150.
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