  We analyze ground-state properties of strictly one-dimensional molecular
matter comprised of identical particles of mass m. Such a class of systems can
be described by an additive two-body potential whose functional form is common
to all substances which only differ in the energy \epsilon and range l scales
of the potential. With this choice De Boer's quantum theorem of corresponding
states holds thus implying that ground-state properties expressed in
appropriate reduced form are only determined by the dimensionless parameter
\lambda_{0}^{2} \sim \hbar^{2}/ml^{2}\epsilon measuring the strength of
zero-point motion in the system. The presence of a minimum in the two-body
interaction potential leads to a many-body bound state which is a Luttinger
liquid. As \lambda_{0} increases, the asymmetry of the two-body potential
causes quantum expansion, softening, and eventual evaporation of the Luttinger
liquid into a gas phase. Selecting the pair interaction potential in the Morse
form we analytically compute the properties of the Luttinger liquid and its
range of existence. As lambda_{0} increases, the system first undergoes a
discontinuous evaporation transition into a diatomic gas followed by a
continuous dissociation transition into a monoatomic gas. In particular we find
that spin-polarized isotopes of hydrogen and He-3 are monoatomic gases, He-4 is
a diatomic gas, while molecular hydrogen and heavier substances are Luttinger
liquids. We also investigate the effect of finite pressure on the properties of
the liquid and monoatomic gas phases. In particular we estimate a pressure at
which molecular hydrogen undergoes an inverse Peierls transition into a
metallic state which is a one-dimensional analog of the transition predicted by
Wigner and Huntington in 1935.
