не ... него

The conjunction него in this construction serves a corrective function (супротстављање са исправљањем или супституцијом).

Key Grammatical Rules:

• Negative Trigger: The first component must carry negative polarity via an overt negated verb or negative particle (such as не, није, немам), which may also be reinforced by negative pronouns via negative concord (нико није, ништа не). Negation can be sentential—marked directly on the finite verb (Нисам разговарао са Марком, него са Јованом), which is predominant in spontaneous speech—or it can function as constituent negation placed directly before a non-verbal element when the focus is narrowly contrastive (Разговарао сам не са Марком, него са Јованом). In standard Serbian, constituent negation is grammatical and common in contrastive, formal, academic, and literary registers.
• Grammatical Parallelism and Prepositions: If you contrast phrases or individual arguments rather than full clauses, the element introduced by него must match the case and syntactic role of the negated element (e.g., Dative replaces Dative, Accusative replaces Accusative). Standard Serbian requires the repetition of governing prepositions with contrastive coordinates (e.g., Нисам путовао у Београд, него у Нови Сад; Није умро од туге, него од болести; Нисам разговарао са Марком, него са Јованом). Omitting the governing preposition after motion or preposition-bound verbs (e.g., *Нисам путовао у Београд, него Нови Сад) results in an ungrammatical or substandard phrasing; full prepositional parallelism is essential.
• Clause vs. Phrase: It works across entire clauses (Нисмо отишли возом, него смо изнајмили аутомобил) or parallel constituents (Не мени, него њему).
• Punctuation Guidelines: Standard Serbian orthography (Правопис српскога језика) classifies corrective него as an adversative conjunction (супротни везник). As a rule, a comma is placed before него both between contrasting clauses (Нисмо путовали возом, него смо остали код куће) and between parallel sentence elements at the phrase level (Није он, него ја; Не обраћам се њему, него вама; Нисам наручио чај, него кафу). However, Правопис specifies an important exception: when the first clause is structurally or semantically incomplete without the second and both form an unbroken intonational and communicative whole, no comma is written (e.g., Нисмо дошли да се одмарамо него да радимо; Није реч о новцу него о поверењу). Do not confuse this corrective use with comparative него ('than'), which does not take a comma (e.g., Бољи је него пре).

Nuance Distinctions:

• него vs. али: Али introduces concession ('A is true, yet B is also true'). It cannot substitute items directly (*Нисам купио кафу, али чај is ungrammatical; use него).
• Reversing the Order (а не): If you state the affirmative correction first and place the rejected alternative second ('X, not Y'), Serbian cannot use него. Instead, it requires , а не (e.g., Разговарао сам са Јованом, а не са Марком; Купио сам чај, а не кафу).
• него vs. већ: Both express substitution after negation. However, већ is more formal, literary, or journalistic, whereas него is standard across all registers, including everyday speech.
• Exclusive vs. Additive: Do not confuse exclusive не ... него ('not X, but Y') with the correlative addition не само ... него и ('not only X, but also Y').