We develop computational tools for spectral analysis of stochastic networks representing energy landscapes of atomic and molecular clusters. Physical meaning and some properties of eigenvalues, left and right eigenvectors, and eigencurrents are discussed. We propose an approach to compute a collection of eigenpairs and corresponding eigencurrents describing the most important relaxation processes taking place in the system on its way to the equilibrium. It is suitable for large and complex stochastic networks where pairwise transition rates, given by the Arrhenius law, vary by orders of magnitude. The proposed methodology is applied to the network representing the Lennard-Jones-38 cluster created by Wales's group. Its energy landscape has a double funnel structure with a deep and narrow face-centered cubic funnel and a shallower and wider icosahedral funnel. Contrary to the expectations, there is no appreciable spectral gap separating the eigenvalue corresponding to the escape from the icosahedral funnel. We provide a detailed description of the escape process from the icosahedral funnel using the eigencurrent and demonstrate a superexponential growth of the corresponding eigenvalue. The proposed spectral approach is compared to the methodology of the Transition Path Theory. Finally, we discuss whether the Lennard-Jones-38 cluster is metastable from the points of view of a mathematician and a chemical physicist, and make a connection with experimental works. Modeling by means of stochastic networks has become widespread in chemical physics. Efficient methods for the conversion of energy landscapes into stochastic networks have been developed. Wales's group constructed a large number of networks representing energy landscapes of atomic and molecular clusters and proteins [55,58,53]. A number of researchers developed efficient techniques for constructing continuous-time Markov chains representing coarse grained dynamics of biomolecules and protein folding called Markov State Models [44,47,20,10,39,40,43,46]. Stochastic networks are attractive for analysis. On one hand, they are more mathematically tractable than the original continuous systems. On the other hand, they are designed to preserve important features of the underlying systems. Nevertheless, analysis of large and complex networks still presents a challenge. The numbers of states (vertices) and edges can be of the order of 10 n , n = 3, 4, 5, 6, ..., and the pairwise transition rates may vary by tens of orders of magnitude. The study of such networks motivates development of new techniques and leads to a new level of understanding of complex systems.In this work, we focus on developing a methodology for computing eigenvalues, eigenvectors, and eigencurrents for networks representing energy landscapes whose pairwise transition rates are given by the Arrhenius law. The spectral decomposition of the generator matrix of a