Gold complexes and nanoparticles exhibit fascinating properties and have found various applications recent years. [1, 2] The chemistry of gold, significantly different from that of its congeners (silver and copper), is mostly dominated by its extraordinarily strong relativistic effects, [3] which impose a very small energy gap between its 5d and 6s valence orbitals and, consequently, a high degree of sd hybridization as well as an even higher electronegativity than that of the nonmetal monovalent hydrogen, that is, Au 2.54 versus H 2.20 (Pauling scale). [4] The concept of gold-hydrogen analogy thus emerged [5] and has been extensively exploited in synthetic chemistry. [1,6] Since the isolobal analogy [7] between phosphine-ligated gold (AuPR 3 ) and hydrogen (H) was noticed by Mingos [5a] in mid 1970s, the use of the AuPR 3 synthon has brought out to a large number of Au-containing metal cluster compounds. [1,6] Key examples are [O(AuPPh 3 ) n ] (nÀ2)+ (n = 3,4), [8] [N(AuPPh 3 ) n ] (nÀ3)+ (n = 4, 5), [9] [C(AuPPh 3 ) n ] (nÀ4)+ (n = 4-6), [10] and [N 2 (AuPR 3 ) 6 ] 2+ , [11] which are analogous to [OH n ] (nÀ2)+ (n = 3,4), [NH n ] (nÀ3)+ (n = 4, 5), [CH n ] (nÀ4)+ (n = 4-6), and hydrazinium [H 3 N À NH 3 ] 2+ , respectively. On the other hand, a simple gold-hydrogen analogy was recently observed in a series of binary Si/Au clusters [Si m Au n ] (m = 1,2; n = 2-4) in the gas phase by Wang and co-workers. [12] Herein we report a joint experimental and theoretical investigation on a series of abundant Au/N binary cluster cations, [AuN 4 ] + , [Au n N 2n+1 ] + (n = 2-4), and [Au 3 N 6 ] + , which exist as dinitrogen-ligated aurodiazenylium [(N 2 (AuN 2 )] + , auronitrenium [N(AuN 2 ) 2 ] + , auroammonia radical cation [N(AuN 2 ) 3 ] + , auroammonium [N(AuN 2 ) 4 ] + , and triaurum cation [(AuN 2 ) 3 ] + , and are struc-turally and electronically analogous to diazenylium ([N 2 H] + ), [13] nitrenium ([NH 2 ] + ), [14] ammonia radical cation ([NH 3 ] + ), [15] ammonium ([NH 4 ] + ), and trihydrogen cation ([H 3 ] + ), [16] respectively, by following the isolobal analogy between N 2 -ligated gold (AuN 2 ) and hydrogen. The chemical stability of these N 2 -ligated complexes suggests that they might be viable in wet chemistry. Such a N 2 -assisted goldhydrogen analogy involving a [AuN 2 ] + synthon and covalent dative Au + ÀN 2 bond is also relevant to the industrially important nitrogen fixation. Figure 1 displays the mass spectrum (180 < m/e < 1000 amu) of [Au p N q ] + clusters obtained by reactive collision of N 2 with laser-vaporized gold clusters. The strong mass spectral peaks for [AuN 4 ] + , [Au 2 N 5 ] + , [Au 3 N 6 ] + , and [Au 4 N 9 ] + indicate that these "magic-number" cations are the most abundant for the positive cluster distribution. Furthermore, the signal intensity of [Au 3 N 7 ] + , a radical cation, is comparable to that of [Au 2 N 5 ] + , likely owing to the high stability of its neutral form, Au 3 N 7 . Moreover, the intense signals of [Au m N (2m+1) ] + (m = 2-4) with odd numbers of N atom...