Calculations at the HF16-31G*; MP2(FC)/6-31G*, and B3LYP/6-31G* levels of theory predict the existence of three pairs of enantiomeric conformers on the potential energy surface of n-Si4Cl10: transoid, ortho, and gauche. At the fully optimized MP2(FC)/6-31G* level the SiSiSiSi dihedral angles (deg) and relative energies (kcal/mol) are 160.5 degrees and 0.0 (transoid), 93.0 degrees and 0.65 (ortho), and 48.7 degrees and 0.27 (gauche). Matrix annealing, spectral differencing, and singular value decomposition analyses of Raman and mid-IR spectra of n-Si4Cl10 in nitrogen matrix demonstrate that three distinct backbone conformers are indeed trapped in the matrices and interconvert upon annealing. Their initial relative concentrations and the derails of the annealing behavior depend on the matrix isolation ratio. Their vibrational spectra have been assigned by comparison with results of MP2(FC)/6-31G* calculations and the nature of the normal modes has been analyzed in terms of calculated potential energy distributions. Annealing in concentrated matrices (N-2:n-Si4Cl10 similar to 200:1) indicates that at least in some environments, the relative stability of the conformers increases in the order gauche < ortho < transoid, in agreement with results of HF/6-31G* and B3LYP/6-31G* calculations.