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Which actinoid metals have the same crystal structure as some lanthanoid metals?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — actinoid element Modern version of the periodic table of the elements (printable).

Several actinoid metals share the same crystal structure as many lanthanoid metals. Specifically, the metals actinium, americium, curium, berkelium, and californium exhibit the same crystal structure as many of the lanthanoids.1

Additionally, einsteinium, which is the heaviest actinoid element with isotopes stable enough for macroscopic chemical study, possesses the same crystal structure as the lanthanoid europium.1

In contrast, the lighter actinoid elements—ranging from thorium through plutonium—typically display different and more complex metallic structures. This variation is attributed to the mixing of 5f and 6d orbitals, which creates hybrid electronic states of nearly identical energy. Beginning with americium, the electron energy levels become sufficiently separated to prevent this mixing, leading to the more consistent crystal structures observed in the heavier actinoids.1