SNIP measures contextual citation impact by weighting citations based on the total number of citations in a subject field.
SJR is a prestige metric based on the idea that not all citations are the same. SJR uses a similar algorithm as the Google page rank; it provides a quantitative and a qualitative measure of the journal’s impact.
The Impact Factor measures the average number of citations received in a particular year by papers published in the journal during the two preceding years.
© Thomson Reuters Journal Citation Reports 2015
To calculate the five year Impact Factor, citations are counted in 2014 to the previous five years and divided by the source items published in the previous five years.
© Journal Citation Reports 2015, Published by Thomson Reuters
Surface Science Reports contains invited review papers on experimental and theoretical studies in the physics, chemistry and pioneering applications of surfaces, interfaces and nanostructures. It covers topics which contribute to a better understanding of basic phenomena occurring on surfaces and interfaces, but also the application of this knowledge to the development of materials, processes and devices. "Surfaces" is defined in this journal to include all interfaces between solids, liquids, polymers, biomaterials, nanostructures, soft matter, gases and/or vacuum. The journal also contains reviews of experimental techniques and methods used to characterize surfaces and surface processes, e.g. those based upon the interactions of photons, electrons and ions with surfaces.