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We have used spectra of hot stars from the RAVE Survey in order to investigate the visibility and properties of five diffuse interstellar bands previously reported in the literature. The RAVE spectroscopic survey for Galactic structure and kinematics records CCD spectra covering the 8400-8800 Ang wavelength region at 7500 resolving power. The spectra are obtained with the UK Schmidt at the AAO, equipped with the 6dF multi-fiber positioner. The DIB at 8620.4 Ang is by far the strongest and cleanest of all DIBs occurring within the RAVE wavelength range, with no interference by underlying absorption stellar lines in hot stars. It correlates so tightly with reddening that it turns out to be a reliable tool to measure it, following the relation E(B-V) = 2.72 (+/- 0.03) x E.W.(Ang), valid throughout the general interstellar medium of our Galaxy. The presence of a DIB at 8648 Ang is confirmed. Its intensity appears unrelated to reddening, in agreement with scanty and preliminary reports available in the literature, and its measurability is strongly compromised by severe blending with underlying stellar HeI doublet at 8649 Ang. The two weak DIBS at 8531 and 8572 Ang do not appear real and should actually be blends of underlying stellar lines. The very weak DIB at 8439 Ang cannot be resolved within the profile of the much stronger underlying hydrogen Paschen 18 stellar line., Accepted in press by A&A

Based on the Bica et al. (1999) catalogue we studied the star cluster system of the LMC and provide a new catalogue of all binary and multiple cluster candidates found. We performed Monte Carlo simulations and produced artificial cluster distributions that we compared with the real one in order to check how many of the found cluster pairs and groups can be expected statistically due to chance superposition on the plane of the sky. We found that, depending on the cluster density, between 56% (bar region) and 12% (outer LMC) of the detected pairs can be explained statistically. We studied in detail the properties of the multiple cluster candidates. The binary cluster candidates seem to show a tendency to form with components of similar size. When possible, we studied the age structure of the cluster groups and found that the multiple clusters are predominantly young with only a few cluster groups older than 300 Myr. The spatial distribution of the cluster pairs and groups coincides with the distribution of clusters in general; however, old groups or groups with large internal age differences are mainly located in the densely populated bar region. Thus, they can easily be explained as chance superpositions. Our findings show that a formation scenario through tidal capture is not only unlikely due to the low probability of close encounters of star clusters, and thus the even lower probability of tidal capture, but the few groups with large internal age differences can easily be explained with projection effects. We favour a formation scenario as suggested by Fujimoto & Kumai (1997) in which the components of a binary cluster formed together and thus should be coeval or have small age differences compatible with cluster formation time scales., 19 pages, including 15 figures, accepted for publication in A&A, minor corrections (1 reference removed form the abstract)