Low-energy spectra in the isotopic chain ${}^{250-262}\mathrm{No}$ are systematically investigated within the fully self-consistent Quasiparticle Random-Phase-Approximation (QRPA) using Skyrme forces SLy4, SLy6, SkM*, and SVbas. QRPA states of multipolarity $\lambda \mu =20$, 22, 30, 31, 32, 33, 43, 44, and 98 are considered. The main attention is paid to isotopes ${}^{252}\mathrm{No}$ and ${}^{254}\mathrm{No}$ where the most extensive experimental spectroscopic information is available. In these two nuclei, a reasonable description of $K^{\pi }=8^{-},2^{-}$, and $3^{+}$ isomers is obtained with forces SLy4 and SLy6. The disputed $8^{-}$ isomer in ${}^{254}\mathrm{No}$ is assigned as neutron two-quasiparticle configuration $nn[734\uparrow ,613\uparrow ]$. The isomers are additionally analyzed using Skyrme functionals UNEDF1, UNEDF2, and ${\mathrm{UNEDF1}}^{\mathrm{SO}}$. At the energies 1.2–1.4 MeV, the 2qp $K$ isomers $4^{-},7^{-}$ in ${}^{252}\mathrm{No}$ and $4^{-},6^{-},7^{-}$ in ${}^{254}\mathrm{No}$ are also predicted. In ${}^{254}\mathrm{No}$, the $K^{\pi }=3^{+}$ isomer should be accompanied by the nearby $K^{\pi }=4^{+}$ counterpart. It is shown that, in the chain ${}^{250-262}\mathrm{No}$, some features of ${}^{252}\mathrm{No}$ and ${}^{254}\mathrm{No}$ should exhibit essential irregularities caused by a noticeable shell gap in the neutron single-particle spectrum and corresponding reduction of the neutron pairing. In particular, low-energy pairing vibrational $K^{\pi }=0^{+}$ states in ${}^{252,254}\mathrm{No}$ are predicted.

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• Collective levels
• Electromagnetic transitions
• Energy levels
• Nuclear density functional theory
• Nuclear structure & decays
• A ≥ 220