Which of the following electronic configuration does not belongs to d-block ?[Xe] 6s2 5d1[Rn] 7s2 6d1[Rn] 7s2 6d2[Xe] 6s2 5d2 4f14

To determine which electronic configuration does not belong to the d-block, we first need to understand what the d-block is. The d-block elements are those whose electron configurations include d subshells, typically where the d orbitals are being filled.

Analyzing the Given Configurations:

1. [Xe] 6s² 5d¹: This configuration belongs to the d-block since it includes the 5d subshell.
2. [Rn] 7s² 6d¹: This configuration also belongs to the d-block because it features the 6d subshell.
3. [Rn] 7s² 6d²: Similar to above, it includes the 6d subshell, thus it's in the d-block.
4. [Xe] 6s² 5d² 4f¹⁴: This configuration includes 5d subshell and an f orbital (4f¹⁴), classifying it within the d-block elements as well.

Conclusion

All provided configurations include d orbitals; however, d-block elements are typically defined by the progressive filling of d subshells. A closer examination shows that the configurations that contain substantial representations of both f and d electrons typically align with f-block (lanthanides/actinides).

Final Answer

None of these configurations truly exclude features of the d-block per traditional definitions; they all pertain to d-block characteristics. However, if we were to select the configuration where d-block characteristics are less pronounced, the one that distinctly emphasizes heavy lifters in f and negligible d may be considered contextually as an aberration. Discussions on d-block demarcation can sometimes suggest that configurations with more significant f-orbital representation pertain less to d-block. Thus, given the conditions and typical conventions of interpretation:

• [Xe] 6s² 5d² 4f¹⁴ could arguably be perceived as slightly deviating in effectual representation compared to the predominate d classifications, owing particularly to its f orbital prominence.