Liquid and amorphous metals are represented by a system of $N_{M}$ clusters $K_{j}$ of interior ($v$) and surface (s) cations. $K_{j}$ are separated by hollows ($h_{j}$) with band electrons. The quantum theory proceeds from the band ($t$) and Coulomb ($Q$) bonds for nontransition metals. In transition liquid metals, the covalent bonds ($\Gamma$) and chemical bonds’ fluctuations (CBF) are added. The Brownian motion and diffusion coefficient $D(T)$ as the functions of temperature $T$ are connected with entropy $S$ of clusters and band electrons. The melting is modelled taking into account $S(N_{M})$. The temperature of this phase transition of first kind $T_{L}(\Gamma, Q, t)$ is integrally expressed through the energies of band quasi-particles, $\varepsilon_{k}$, and CBF. Constant magnetic field manifests $3d$-clusters in nontransition liquid metals (Ga, Sn, ...). Variable field $B(\omega)$ with frequency $\omega \geq 10^{3}$ separates the surface and the bulk of alloy due to skin effect. Light impurities (C, O, ...) change the composition of liquid alloy and its spectra, when they enter into reactions in the presence of thermal and electromagnetic fields.